/*
 * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef WebFrameClient_h
#define WebFrameClient_h

#include "WebAXObject.h"
#include "WebDOMMessageEvent.h"
#include "WebDataSource.h"
#include "WebFileChooserParams.h"
#include "WebFormElement.h"
#include "WebFrame.h"
#include "WebFrameOwnerProperties.h"
#include "WebHistoryCommitType.h"
#include "WebHistoryItem.h"
#include "WebIconURL.h"
#include "WebNavigationPolicy.h"
#include "WebNavigationType.h"
#include "WebNavigatorContentUtilsClient.h"
#include "WebSandboxFlags.h"
#include "WebTextDirection.h"
#include "public/platform/BlameContext.h"
#include "public/platform/WebColor.h"
#include "public/platform/WebCommon.h"
#include "public/platform/WebContentSecurityPolicy.h"
#include "public/platform/WebContentSecurityPolicyStruct.h"
#include "public/platform/WebEffectiveConnectionType.h"
#include "public/platform/WebFeaturePolicy.h"
#include "public/platform/WebFileSystem.h"
#include "public/platform/WebFileSystemType.h"
#include "public/platform/WebInsecureRequestPolicy.h"
#include "public/platform/WebLoadingBehaviorFlag.h"
#include "public/platform/WebPageVisibilityState.h"
#include "public/platform/WebSecurityOrigin.h"
#include "public/platform/WebSetSinkIdCallbacks.h"
#include "public/platform/WebSourceLocation.h"
#include "public/platform/WebStorageQuotaCallbacks.h"
#include "public/platform/WebStorageQuotaType.h"
#include "public/platform/WebURLError.h"
#include "public/platform/WebURLRequest.h"
#include "public/platform/WebWorkerFetchContext.h"
#include "v8/include/v8.h"

namespace blink {

enum class WebTreeScopeType;
class WebApplicationCacheHost;
class WebApplicationCacheHostClient;
class WebColorChooser;
class WebColorChooserClient;
class WebContentDecryptionModule;
class WebCookieJar;
class WebDataSource;
class WebEncryptedMediaClient;
class WebExternalPopupMenu;
class WebExternalPopupMenuClient;
class WebFileChooserCompletion;
class WebLocalFrame;
class WebMediaPlayer;
class WebMediaPlayerClient;
class WebMediaPlayerEncryptedMediaClient;
class WebMediaPlayerSource;
class WebMediaSession;
class WebServiceWorkerProvider;
class WebPlugin;
class WebPresentationClient;
class WebPushClient;
class WebRTCPeerConnectionHandler;
class WebRelatedAppsFetcher;
class WebScreenOrientationClient;
class WebString;
class WebURL;
class WebURLResponse;
class WebUserMediaClient;
class WebWorkerContentSettingsClientProxy;
struct WebColorSuggestion;
struct WebConsoleMessage;
struct WebContextMenuData;
struct WebPluginParams;
struct WebPopupMenuInfo;
struct WebRect;
struct WebURLError;

class BLINK_EXPORT WebFrameClient {
 public:
  virtual ~WebFrameClient() {}

  // Factory methods -----------------------------------------------------

  // May return null.
  virtual WebPlugin* CreatePlugin(WebLocalFrame*, const WebPluginParams&) {
    return 0;
  }

  // May return null.
  // WebContentDecryptionModule* may be null if one has not yet been set.
  virtual WebMediaPlayer* CreateMediaPlayer(const WebMediaPlayerSource&,
                                            WebMediaPlayerClient*,
                                            WebMediaPlayerEncryptedMediaClient*,
                                            WebContentDecryptionModule*,
                                            const WebString& sink_id) {
    return 0;
  }

  // May return null.
  virtual WebMediaSession* CreateMediaSession() { return 0; }

  // May return null.
  virtual WebApplicationCacheHost* CreateApplicationCacheHost(
      WebApplicationCacheHostClient*) {
    return 0;
  }

  // May return null.
  virtual WebServiceWorkerProvider* CreateServiceWorkerProvider() { return 0; }

  // May return null.
  virtual WebWorkerContentSettingsClientProxy*
  CreateWorkerContentSettingsClientProxy() {
    return 0;
  }

  // Returns a new WebWorkerFetchContext for a dedicated worker. Ownership of
  // the returned object is transferred to the caller. This is used only when
  // off-main-thread-fetch is enabled.
  virtual std::unique_ptr<WebWorkerFetchContext> CreateWorkerFetchContext() {
    return nullptr;
  }

  // Create a new WebPopupMenu. In the "createExternalPopupMenu" form, the
  // client is responsible for rendering the contents of the popup menu.
  virtual WebExternalPopupMenu* CreateExternalPopupMenu(
      const WebPopupMenuInfo&,
      WebExternalPopupMenuClient*) {
    return 0;
  }

  // Services ------------------------------------------------------------

  // A frame specific cookie jar.  May return null, in which case
  // WebKitPlatformSupport::cookieJar() will be called to access cookies.
  virtual WebCookieJar* CookieJar() { return 0; }

  // Returns a blame context for attributing work belonging to this frame.
  virtual BlameContext* GetFrameBlameContext() { return nullptr; }

  // General notifications -----------------------------------------------

  // Indicates if creating a plugin without an associated renderer is supported.
  virtual bool CanCreatePluginWithoutRenderer(const WebString& mime_type) {
    return false;
  }

  // Indicates that another page has accessed the DOM of the initial empty
  // document of a main frame. After this, it is no longer safe to show a
  // pending navigation's URL, because a URL spoof is possible.
  virtual void DidAccessInitialDocument() {}

  // Request the creation of a new child frame. Embedders may return nullptr
  // to prevent the new child frame from being attached. Otherwise, embedders
  // should create a new WebLocalFrame, insert it into the frame tree, and
  // return the created frame.
  virtual WebLocalFrame* CreateChildFrame(
      WebLocalFrame* parent,
      WebTreeScopeType,
      const WebString& name,
      const WebString& fallback_name,
      WebSandboxFlags sandbox_flags,
      const WebParsedFeaturePolicy& container_policy,
      const WebFrameOwnerProperties&) {
    return nullptr;
  }

  // This frame has set its opener to another frame, or disowned the opener
  // if opener is null. See http://html.spec.whatwg.org/#dom-opener.
  virtual void DidChangeOpener(WebFrame*) {}

  // Specifies the reason for the detachment.
  enum class DetachType { kRemove, kSwap };

  // This frame has been detached. Embedders should release any resources
  // associated with this frame. If the DetachType is Remove, the frame should
  // also be removed from the frame tree; otherwise, if the DetachType is
  // Swap, the frame is being replaced in-place by WebFrame::swap().
  virtual void FrameDetached(WebLocalFrame*, DetachType);

  // This frame has become focused.
  virtual void FrameFocused() {}

  // A provisional load is about to commit.
  virtual void WillCommitProvisionalLoad() {}

  // This frame's name has changed.
  virtual void DidChangeName(const WebString& name) {}

  // This frame has set an insecure request policy.
  virtual void DidEnforceInsecureRequestPolicy(WebInsecureRequestPolicy) {}

  // This frame has been updated to a unique origin, which should be
  // considered potentially trustworthy if
  // |isPotentiallyTrustworthyUniqueOrigin| is true. TODO(estark):
  // this method only exists to support dynamic sandboxing via a CSP
  // delivered in a <meta> tag. This is not supposed to be allowed per
  // the CSP spec and should be ripped out. https://crbug.com/594645
  virtual void DidUpdateToUniqueOrigin(
      bool is_potentially_trustworthy_unique_origin) {}

  // The sandbox flags or container policy have changed for a child frame of
  // this frame.
  virtual void DidChangeFramePolicy(
      WebFrame* child_frame,
      WebSandboxFlags flags,
      const WebParsedFeaturePolicy& container_policy) {}

  // Called when a Feature-Policy HTTP header is encountered while loading the
  // frame's document.
  virtual void DidSetFeaturePolicyHeader(
      const WebParsedFeaturePolicy& parsed_header) {}

  // Called when a new Content Security Policy is added to the frame's
  // document.  This can be triggered by handling of HTTP headers, handling
  // of <meta> element, or by inheriting CSP from the parent (in case of
  // about:blank).
  virtual void DidAddContentSecurityPolicies(
      const WebVector<WebContentSecurityPolicy>& policies) {}

  // Some frame owner properties have changed for a child frame of this frame.
  // Frame owner properties currently include: scrolling, marginwidth and
  // marginheight.
  virtual void DidChangeFrameOwnerProperties(WebFrame* child_frame,
                                             const WebFrameOwnerProperties&) {}

  // Called when a watched CSS selector matches or stops matching.
  virtual void DidMatchCSS(
      const WebVector<WebString>& newly_matching_selectors,
      const WebVector<WebString>& stopped_matching_selectors) {}

  // Called the first time this frame is the target of a user gesture.
  virtual void SetHasReceivedUserGesture() {}

  // Console messages ----------------------------------------------------

  // Whether or not we should report a detailed message for the given source.
  virtual bool ShouldReportDetailedMessageForSource(const WebString& source) {
    return false;
  }

  // A new message was added to the console.
  virtual void DidAddMessageToConsole(const WebConsoleMessage&,
                                      const WebString& source_name,
                                      unsigned source_line,
                                      const WebString& stack_trace) {}

  // Load commands -------------------------------------------------------

  // The client should handle the navigation externally.
  virtual void LoadURLExternally(const WebURLRequest&,
                                 WebNavigationPolicy,
                                 const WebString& download_name,
                                 bool should_replace_current_entry) {}

  // The client should load an error page in the current frame.
  virtual void LoadErrorPage(int reason) {}

  // Navigational queries ------------------------------------------------

  // The client may choose to alter the navigation policy.  Otherwise,
  // defaultPolicy should just be returned.

  struct NavigationPolicyInfo {
    WebDataSource::ExtraData* extra_data;

    // Note: if browser side navigations are enabled, the client may modify
    // the urlRequest. However, should this happen, the client should change
    // the WebNavigationPolicy to WebNavigationPolicyIgnore, and the load
    // should stop in blink. In all other cases, the urlRequest should not
    // be modified.
    WebURLRequest& url_request;
    WebNavigationType navigation_type;
    WebNavigationPolicy default_policy;
    bool replaces_current_history_item;
    bool is_history_navigation_in_new_child_frame;
    bool is_client_redirect;
    WebFormElement form;
    bool is_cache_disabled;
    WebSourceLocation source_location;
    WebContentSecurityPolicyDisposition
        should_check_main_world_content_security_policy;

    NavigationPolicyInfo(WebURLRequest& url_request)
        : extra_data(nullptr),
          url_request(url_request),
          navigation_type(kWebNavigationTypeOther),
          default_policy(kWebNavigationPolicyIgnore),
          replaces_current_history_item(false),
          is_history_navigation_in_new_child_frame(false),
          is_client_redirect(false),
          is_cache_disabled(false),
          should_check_main_world_content_security_policy(
              kWebContentSecurityPolicyDispositionCheck) {}
  };

  virtual WebNavigationPolicy DecidePolicyForNavigation(
      const NavigationPolicyInfo& info) {
    return info.default_policy;
  }

  // During a history navigation, we may choose to load new subframes from
  // history as well.  This returns such a history item if appropriate.
  virtual WebHistoryItem HistoryItemForNewChildFrame() {
    return WebHistoryItem();
  }

  // Asks the embedder whether the frame is allowed to navigate the main frame
  // to a data URL.
  // TODO(crbug.com/713259): Move renderer side checks to
  //                         RenderFrameImpl::DecidePolicyForNavigation().
  virtual bool AllowContentInitiatedDataUrlNavigations(const WebURL&) {
    return false;
  }

  // Navigational notifications ------------------------------------------

  // These notifications bracket any loading that occurs in the WebFrame.
  virtual void DidStartLoading(bool to_different_document) {}
  virtual void DidStopLoading() {}

  // Notification that some progress was made loading the current frame.
  // loadProgress is a value between 0 (nothing loaded) and 1.0 (frame fully
  // loaded).
  virtual void DidChangeLoadProgress(double load_progress) {}

  // A form submission has been requested, but the page's submit event handler
  // hasn't yet had a chance to run (and possibly alter/interrupt the submit.)
  virtual void WillSendSubmitEvent(const WebFormElement&) {}

  // A form submission is about to occur.
  virtual void WillSubmitForm(const WebFormElement&) {}

  // A datasource has been created for a new navigation.  The given
  // datasource will become the provisional datasource for the frame.
  virtual void DidCreateDataSource(WebLocalFrame*, WebDataSource*) {}

  // A new provisional load has been started.
  virtual void DidStartProvisionalLoad(WebDataSource* data_source,
                                       WebURLRequest& request) {}

  // The provisional load was redirected via a HTTP 3xx response.
  virtual void DidReceiveServerRedirectForProvisionalLoad() {}

  // The provisional load failed. The WebHistoryCommitType is the commit type
  // that would have been used had the load succeeded.
  virtual void DidFailProvisionalLoad(const WebURLError&,
                                      WebHistoryCommitType) {}

  // The provisional datasource is now committed.  The first part of the
  // response body has been received, and the encoding of the response
  // body is known.
  virtual void DidCommitProvisionalLoad(const WebHistoryItem&,
                                        WebHistoryCommitType) {}

  // The frame's document has just been initialized.
  virtual void DidCreateNewDocument(WebLocalFrame* frame) {}

  // The window object for the frame has been cleared of any extra
  // properties that may have been set by script from the previously
  // loaded document.
  virtual void DidClearWindowObject() {}

  // The document element has been created.
  // This method may not invalidate the frame, nor execute JavaScript code.
  virtual void DidCreateDocumentElement(WebLocalFrame*) {}

  // Like |didCreateDocumentElement|, except this method may run JavaScript
  // code (and possibly invalidate the frame).
  virtual void RunScriptsAtDocumentElementAvailable(WebLocalFrame*) {}

  // The page title is available.
  virtual void DidReceiveTitle(const WebString& title,
                               WebTextDirection direction) {}

  // The icon for the page have changed.
  virtual void DidChangeIcon(WebIconURL::Type) {}

  // The frame's document finished loading.
  // This method may not execute JavaScript code.
  virtual void DidFinishDocumentLoad(WebLocalFrame*) {}

  // Like |didFinishDocumentLoad|, except this method may run JavaScript
  // code (and possibly invalidate the frame).
  virtual void RunScriptsAtDocumentReady(bool document_is_empty) {}

  // The frame's window.onload event is ready to fire. This method may delay
  // window.onload by incrementing LoadEventDelayCount.
  virtual void RunScriptsAtDocumentIdle() {}

  // The 'load' event was dispatched.
  virtual void DidHandleOnloadEvents() {}

  // The frame's document or one of its subresources failed to load. The
  // WebHistoryCommitType is the commit type that would have been used had the
  // load succeeded.
  virtual void DidFailLoad(const WebURLError&, WebHistoryCommitType) {}

  // The frame's document and all of its subresources succeeded to load.
  virtual void DidFinishLoad() {}

  // The navigation resulted in no change to the documents within the page.
  // For example, the navigation may have just resulted in scrolling to a
  // named anchor or a PopState event may have been dispatched.
  virtual void DidNavigateWithinPage(const WebHistoryItem&,
                                     WebHistoryCommitType,
                                     bool content_initiated) {}

  // Called upon update to scroll position, document state, and other
  // non-navigational events related to the data held by WebHistoryItem.
  // WARNING: This method may be called very frequently.
  virtual void DidUpdateCurrentHistoryItem() {}

  // The frame's manifest has changed.
  virtual void DidChangeManifest() {}

  // The frame's theme color has changed.
  virtual void DidChangeThemeColor() {}

  // Called to dispatch a load event for this frame in the FrameOwner of an
  // out-of-process parent frame.
  virtual void DispatchLoad() {}

  // Returns the effective connection type when the frame was fetched.
  virtual WebEffectiveConnectionType GetEffectiveConnectionType() {
    return WebEffectiveConnectionType::kTypeUnknown;
  }

  // PlzNavigate
  // Called to abort a navigation that is being handled by the browser process.
  virtual void AbortClientNavigation() {}

  // Push API ---------------------------------------------------

  // Used to access the embedder for the Push API.
  virtual WebPushClient* PushClient() { return 0; }

  // Presentation API ----------------------------------------------------

  // Used to access the embedder for the Presentation API.
  virtual WebPresentationClient* PresentationClient() { return 0; }

  // InstalledApp API ----------------------------------------------------

  // Used to access the embedder for the InstalledApp API.
  virtual WebRelatedAppsFetcher* GetRelatedAppsFetcher() { return nullptr; }

  // Editing -------------------------------------------------------------

  // These methods allow the client to intercept and overrule editing
  // operations.
  virtual void DidChangeSelection(bool is_selection_empty) {}

  // This method is called in response to handleInputEvent() when the
  // default action for the current keyboard event is not suppressed by the
  // page, to give the embedder a chance to handle the keyboard event
  // specially.
  //
  // Returns true if the keyboard event was handled by the embedder,
  // indicating that the default action should be suppressed.
  virtual bool HandleCurrentKeyboardEvent() { return false; }

  // Dialogs -------------------------------------------------------------

  // This method opens the color chooser and returns a new WebColorChooser
  // instance. If there is a WebColorChooser already from the last time this
  // was called, it ends the color chooser by calling endChooser, and replaces
  // it with the new one. The given list of suggestions can be used to show a
  // simple interface with a limited set of choices.

  virtual WebColorChooser* CreateColorChooser(
      WebColorChooserClient*,
      const WebColor&,
      const WebVector<WebColorSuggestion>&) {
    return 0;
  }

  // Displays a modal alert dialog containing the given message. Returns
  // once the user dismisses the dialog.
  virtual void RunModalAlertDialog(const WebString& message) {}

  // Displays a modal confirmation dialog with the given message as
  // description and OK/Cancel choices. Returns true if the user selects
  // 'OK' or false otherwise.
  virtual bool RunModalConfirmDialog(const WebString& message) { return false; }

  // Displays a modal input dialog with the given message as description
  // and OK/Cancel choices. The input field is pre-filled with
  // defaultValue. Returns true if the user selects 'OK' or false
  // otherwise. Upon returning true, actualValue contains the value of
  // the input field.
  virtual bool RunModalPromptDialog(const WebString& message,
                                    const WebString& default_value,
                                    WebString* actual_value) {
    return false;
  }

  // Displays a modal confirmation dialog with OK/Cancel choices, where 'OK'
  // means that it is okay to proceed with closing the view. Returns true if
  // the user selects 'OK' or false otherwise.
  virtual bool RunModalBeforeUnloadDialog(bool is_reload) { return true; }

  // This method returns immediately after showing the dialog. When the
  // dialog is closed, it should call the WebFileChooserCompletion to
  // pass the results of the dialog. Returns false if
  // WebFileChooseCompletion will never be called.
  virtual bool RunFileChooser(const blink::WebFileChooserParams& params,
                              WebFileChooserCompletion* chooser_completion) {
    return false;
  }

  // UI ------------------------------------------------------------------

  // Shows a context menu with commands relevant to a specific element on
  // the given frame. Additional context data is supplied.
  virtual void ShowContextMenu(const WebContextMenuData&) {}

  // This method is called in response to WebView's saveImageAt(x, y).
  // A data url from <canvas> or <img> is passed to the method's argument.
  virtual void SaveImageFromDataURL(const WebString&) {}

  // Low-level resource notifications ------------------------------------

  // A request is about to be sent out, and the client may modify it.  Request
  // is writable, and changes to the URL, for example, will change the request
  // made.
  virtual void WillSendRequest(WebURLRequest&) {}

  // Response headers have been received.
  virtual void DidReceiveResponse(const WebURLResponse&) {}

  // The specified request was satified from WebCore's memory cache.
  virtual void DidLoadResourceFromMemoryCache(const WebURLRequest&,
                                              const WebURLResponse&) {}

  // This frame has displayed inactive content (such as an image) from an
  // insecure source.  Inactive content cannot spread to other frames.
  virtual void DidDisplayInsecureContent() {}

  // This frame contains a form that submits to an insecure target url.
  virtual void DidContainInsecureFormAction() {}

  // The indicated security origin has run active content (such as a
  // script) from an insecure source.  Note that the insecure content can
  // spread to other frames in the same origin.
  virtual void DidRunInsecureContent(const WebSecurityOrigin&,
                                     const WebURL& insecure_url) {}

  // A reflected XSS was encountered in the page and suppressed.
  virtual void DidDetectXSS(const WebURL&, bool did_block_entire_page) {}

  // A PingLoader was created, and a request dispatched to a URL.
  virtual void DidDispatchPingLoader(const WebURL&) {}

  // This frame has displayed inactive content (such as an image) from
  // a connection with certificate errors.
  virtual void DidDisplayContentWithCertificateErrors(const WebURL& url) {}
  // This frame has run active content (such as a script) from a
  // connection with certificate errors.
  virtual void DidRunContentWithCertificateErrors(const WebURL& url) {}

  // A performance timing event (e.g. first paint) occurred
  virtual void DidChangePerformanceTiming() {}

  // Blink exhibited a certain loading behavior that the browser process will
  // use for segregated histograms.
  virtual void DidObserveLoadingBehavior(WebLoadingBehaviorFlag) {}

  // Script notifications ------------------------------------------------

  // Notifies that a new script context has been created for this frame.
  // This is similar to didClearWindowObject but only called once per
  // frame context.
  virtual void DidCreateScriptContext(WebLocalFrame*,
                                      v8::Local<v8::Context>,
                                      int world_id) {}

  // WebKit is about to release its reference to a v8 context for a frame.
  virtual void WillReleaseScriptContext(WebLocalFrame*,
                                        v8::Local<v8::Context>,
                                        int world_id) {}

  // Geometry notifications ----------------------------------------------

  // The main frame scrolled.
  virtual void DidChangeScrollOffset(WebLocalFrame*) {}

  // If the frame is loading an HTML document, this will be called to
  // notify that the <body> will be attached soon.
  virtual void WillInsertBody(WebLocalFrame*) {}

  // Find-in-page notifications ------------------------------------------

  // Notifies how many matches have been found in this frame so far, for a
  // given identifier.  |finalUpdate| specifies whether this is the last
  // update for this frame.
  virtual void ReportFindInPageMatchCount(int identifier,
                                          int count,
                                          bool final_update) {}

  // Notifies what tick-mark rect is currently selected.   The given
  // identifier lets the client know which request this message belongs
  // to, so that it can choose to ignore the message if it has moved on
  // to other things.  The selection rect is expected to have coordinates
  // relative to the top left corner of the web page area and represent
  // where on the screen the selection rect is currently located.
  virtual void ReportFindInPageSelection(int identifier,
                                         int active_match_ordinal,
                                         const WebRect& selection) {}

  // Quota ---------------------------------------------------------

  // Requests a new quota size for the origin's storage.
  // |newQuotaInBytes| indicates how much storage space (in bytes) the
  // caller expects to need.
  // WebStorageQuotaCallbacks::didGrantStorageQuota will be called when
  // a new quota is granted. WebStorageQuotaCallbacks::didFail
  // is called with an error code otherwise.
  // Note that the requesting quota size may not always be granted and
  // a smaller amount of quota than requested might be returned.
  virtual void RequestStorageQuota(WebStorageQuotaType,
                                   unsigned long long new_quota_in_bytes,
                                   WebStorageQuotaCallbacks) {}

  // MediaStream -----------------------------------------------------

  // A new WebRTCPeerConnectionHandler is created.
  virtual void WillStartUsingPeerConnectionHandler(
      WebRTCPeerConnectionHandler*) {}

  virtual WebUserMediaClient* UserMediaClient() { return 0; }

  // Encrypted Media -------------------------------------------------

  virtual WebEncryptedMediaClient* EncryptedMediaClient() { return 0; }

  // User agent ------------------------------------------------------

  // Asks the embedder if a specific user agent should be used. Non-empty
  // strings indicate an override should be used. Otherwise,
  // Platform::current()->userAgent() will be called to provide one.
  virtual WebString UserAgentOverride() { return WebString(); }

  // Do not track ----------------------------------------------------

  // Asks the embedder what value the network stack will send for the DNT
  // header. An empty string indicates that no DNT header will be send.
  virtual WebString DoNotTrackValue() { return WebString(); }

  // WebGL ------------------------------------------------------

  // Asks the embedder whether WebGL is allowed for the WebFrame. This call is
  // placed here instead of WebContentSettingsClient because this class is
  // implemented in content/, and putting it here avoids adding more public
  // content/ APIs.
  virtual bool AllowWebGL(bool default_value) { return default_value; }

  // Screen Orientation --------------------------------------------------

  // Access the embedder API for (client-based) screen orientation client .
  virtual WebScreenOrientationClient* GetWebScreenOrientationClient() {
    return 0;
  }

  // Accessibility -------------------------------------------------------

  // Notifies embedder about an accessibility event.
  virtual void PostAccessibilityEvent(const WebAXObject&, WebAXEvent) {}

  // Provides accessibility information about a find in page result.
  virtual void HandleAccessibilityFindInPageResult(
      int identifier,
      int match_index,
      const WebAXObject& start_object,
      int start_offset,
      const WebAXObject& end_object,
      int end_offset) {}

  // Fullscreen ----------------------------------------------------------

  // Called to enter/exit fullscreen mode.
  // After calling enterFullscreen or exitFullscreen,
  // WebWidget::didEnterFullscreen or WebWidget::didExitFullscreen
  // respectively will be called once the fullscreen mode has changed.
  virtual void EnterFullscreen() {}
  virtual void ExitFullscreen() {}

  // Sudden termination --------------------------------------------------

  // Called when elements preventing the sudden termination of the frame
  // become present or stop being present. |type| is the type of element
  // (BeforeUnload handler, Unload handler).
  enum SuddenTerminationDisablerType {
    kBeforeUnloadHandler,
    kUnloadHandler,
  };
  virtual void SuddenTerminationDisablerChanged(bool present,
                                                SuddenTerminationDisablerType) {
  }

  // Navigator Content Utils  --------------------------------------------

  // Registers a new URL handler for the given protocol.
  virtual void RegisterProtocolHandler(const WebString& scheme,
                                       const WebURL& url,
                                       const WebString& title) {}

  // Unregisters a given URL handler for the given protocol.
  virtual void UnregisterProtocolHandler(const WebString& scheme,
                                         const WebURL& url) {}

  // Check if a given URL handler is registered for the given protocol.
  virtual WebCustomHandlersState IsProtocolHandlerRegistered(
      const WebString& scheme,
      const WebURL& url) {
    return kWebCustomHandlersNew;
  }

  // Audio Output Devices API --------------------------------------------

  // Checks that the given audio sink exists and is authorized. The result is
  // provided via the callbacks.  This method takes ownership of the callbacks
  // pointer.
  virtual void CheckIfAudioSinkExistsAndIsAuthorized(
      const WebString& sink_id,
      const WebSecurityOrigin&,
      WebSetSinkIdCallbacks* callbacks) {
    if (callbacks) {
      callbacks->OnError(WebSetSinkIdError::kNotSupported);
      delete callbacks;
    }
  }

  // Visibility ----------------------------------------------------------

  // Returns the current visibility of the WebFrame.
  virtual WebPageVisibilityState VisibilityState() const {
    return kWebPageVisibilityStateVisible;
  }

  // Overwrites the given URL to use an HTML5 embed if possible.
  // An empty URL is returned if the URL is not overriden.
  virtual WebURL OverrideFlashEmbedWithHTML(const WebURL& url) {
    return WebURL();
  }
};

}  // namespace blink

#endif