chrome/browser/extensions/content_script_apitest.cc

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stddef.h>

#include "base/bind.h"
#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ptr_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
#include "chrome/browser/extensions/api/permissions/permissions_api.h"
#include "chrome/browser/extensions/extension_apitest.h"
#include "chrome/browser/extensions/extension_service.h"
#include "chrome/browser/extensions/test_extension_dir.h"
#include "chrome/browser/ui/browser.h"
#include "chrome/browser/ui/tabs/tab_strip_model.h"
#include "chrome/common/chrome_switches.h"
#include "chrome/test/base/ui_test_utils.h"
#include "components/app_modal/javascript_dialog_extensions_client.h"
#include "components/app_modal/javascript_dialog_manager.h"
#include "content/public/browser/javascript_dialog_manager.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/web_contents.h"
#include "content/public/browser/web_contents_delegate.h"
#include "content/public/test/browser_test_utils.h"
#include "extensions/browser/notification_types.h"
#include "extensions/common/extension.h"
#include "extensions/test/extension_test_message_listener.h"
#include "extensions/test/result_catcher.h"
#include "net/dns/mock_host_resolver.h"
#include "net/test/embedded_test_server/embedded_test_server.h"
#include "url/gurl.h"

namespace extensions {

namespace {

// A fake webstore domain.
const char kWebstoreDomain[] = "cws.com";

// Check whether or not style was injected, with |expected_injection| indicating
// the expected result. Also ensure that no CSS was added to the
// document.styleSheets array.
testing::AssertionResult CheckStyleInjection(Browser* browser,
                                             const GURL& url,
                                             bool expected_injection) {
  ui_test_utils::NavigateToURL(browser, url);

  bool css_injected = false;
  if (!content::ExecuteScriptAndExtractBool(
          browser->tab_strip_model()->GetActiveWebContents(),
          "window.domAutomationController.send("
          "    document.defaultView.getComputedStyle(document.body, null)."
          "        getPropertyValue('display') == 'none');",
          &css_injected)) {
    return testing::AssertionFailure()
        << "Failed to execute script and extract bool for injection status.";
  }

  if (css_injected != expected_injection) {
    std::string message;
    if (css_injected)
      message = "CSS injected when no injection was expected.";
    else
      message = "CSS not injected when injection was expected.";
    return testing::AssertionFailure() << message;
  }

  bool css_doesnt_add_to_list = false;
  if (!content::ExecuteScriptAndExtractBool(
          browser->tab_strip_model()->GetActiveWebContents(),
          "window.domAutomationController.send("
          "    document.styleSheets.length == 0);",
          &css_doesnt_add_to_list)) {
    return testing::AssertionFailure()
        << "Failed to execute script and extract bool for stylesheets length.";
  }
  if (!css_doesnt_add_to_list) {
    return testing::AssertionFailure()
        << "CSS injection added to number of stylesheets.";
  }

  return testing::AssertionSuccess();
}

class DialogClient;

// A helper class to hijack the dialog manager's ExtensionsClient, so that we
// know when dialogs are being opened.
// NOTE: The default implementation of the JavaScriptDialogExtensionsClient
// doesn't do anything, so it's safe to override it. If, at some stage, this
// has behavior (like if we move this into app shell), we'll need to update
// this (by, e.g., making DialogClient a wrapper around the implementation).
class DialogHelper {
 public:
  explicit DialogHelper(content::WebContents* web_contents);
  ~DialogHelper();

  // Notifies the DialogHelper that a dialog was opened. Runs |quit_closure_|,
  // if it is non-null.
  void DialogOpened();

  // Closes any active dialogs.
  void CloseDialogs();

  void set_quit_closure(const base::Closure& quit_closure) {
    quit_closure_ = quit_closure;
  }
  size_t dialog_count() const { return dialog_count_; }

 private:
  // The number of dialogs to appear.
  size_t dialog_count_;

  // The WebContents this helper is associated with.
  content::WebContents* web_contents_;

  // The dialog manager for |web_contents_|.
  content::JavaScriptDialogManager* dialog_manager_;

  // The dialog client override.
  DialogClient* client_;

  // The quit closure to run when a dialog appears.
  base::Closure quit_closure_;

  DISALLOW_COPY_AND_ASSIGN(DialogHelper);
};

// The client override for the DialogHelper.
class DialogClient : public app_modal::JavaScriptDialogExtensionsClient {
 public:
  explicit DialogClient(DialogHelper* helper) : helper_(helper) {}
  ~DialogClient() override {}

  void set_helper(DialogHelper* helper) { helper_ = helper; }

 private:
  // app_modal::JavaScriptDialogExtensionsClient:
  void OnDialogOpened(content::WebContents* web_contents) override {
    if (helper_)
      helper_->DialogOpened();
  }
  void OnDialogClosed(content::WebContents* web_contents) override {}
  bool GetExtensionName(content::WebContents* web_contents,
                        const GURL& origin_url,
                        std::string* name_out) override {
    return false;
  }

  // The dialog helper to notify of any open dialogs.
  DialogHelper* helper_;

  DISALLOW_COPY_AND_ASSIGN(DialogClient);
};

DialogHelper::DialogHelper(content::WebContents* web_contents)
    : dialog_count_(0),
      web_contents_(web_contents),
      dialog_manager_(nullptr),
      client_(nullptr) {
  app_modal::JavaScriptDialogManager* dialog_manager_impl =
      app_modal::JavaScriptDialogManager::GetInstance();
  client_ = new DialogClient(this);
  dialog_manager_impl->SetExtensionsClient(base::WrapUnique(client_));

  dialog_manager_ =
      web_contents_->GetDelegate()->GetJavaScriptDialogManager(web_contents_);
}

DialogHelper::~DialogHelper() {
  client_->set_helper(nullptr);
}

void DialogHelper::CloseDialogs() {
  dialog_manager_->CancelActiveAndPendingDialogs(web_contents_);
}

void DialogHelper::DialogOpened() {
  ++dialog_count_;
  if (!quit_closure_.is_null()) {
    quit_closure_.Run();
    quit_closure_ = base::Closure();
  }
}

// Runs all pending tasks in the renderer associated with |web_contents|, and
// then all pending tasks in the browser process.
// Returns true on success.
bool RunAllPending(content::WebContents* web_contents) {
  // This is slight hack to achieve a RunPendingInRenderer() method. Since IPCs
  // are sent synchronously, anything started prior to this method will finish
  // before this method returns (as content::ExecuteScript() is synchronous).
  if (!content::ExecuteScript(web_contents, "1 == 1;"))
    return false;
  base::RunLoop().RunUntilIdle();
  return true;
}

// A simple extension manifest with content scripts on all pages.
const char kManifest[] =
    "{"
    "  \"name\": \"%s\","
    "  \"version\": \"1.0\","
    "  \"manifest_version\": 2,"
    "  \"content_scripts\": [{"
    "    \"matches\": [\"*://*/*\"],"
    "    \"js\": [\"script.js\"],"
    "    \"run_at\": \"%s\""
    "  }]"
    "}";

// A (blocking) content script that pops up an alert.
const char kBlockingScript[] = "alert('ALERT');";

// A (non-blocking) content script that sends a message.
const char kNonBlockingScript[] = "chrome.test.sendMessage('done');";

const char kNewTabOverrideManifest[] =
    "{"
    "  \"name\": \"New tab override\","
    "  \"version\": \"0.1\","
    "  \"manifest_version\": 2,"
    "  \"description\": \"Foo!\","
    "  \"chrome_url_overrides\": {\"newtab\": \"newtab.html\"}"
    "}";

const char kNewTabHtml[] = "<html>NewTabOverride!</html>";

}  // namespace

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptAllFrames) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/all_frames")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptAboutBlankIframes) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(
      RunExtensionTest("content_scripts/about_blank_iframes")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptAboutBlankAndSrcdoc) {
  // The optional "*://*/*" permission is requested after verifying that
  // content script insertion solely depends on content_scripts[*].matches.
  // The permission is needed for chrome.tabs.executeScript tests.
  PermissionsRequestFunction::SetAutoConfirmForTests(true);
  PermissionsRequestFunction::SetIgnoreUserGestureForTests(true);

  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/about_blank_srcdoc"))
      << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptExtensionIframe) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/extension_iframe")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptExtensionProcess) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(
      RunExtensionTest("content_scripts/extension_process")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptFragmentNavigation) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  const char extension_name[] = "content_scripts/fragment";
  ASSERT_TRUE(RunExtensionTest(extension_name)) << message_;
}

// Times out on Linux: http://crbug.com/163097
#if defined(OS_LINUX)
#define MAYBE_ContentScriptIsolatedWorlds DISABLED_ContentScriptIsolatedWorlds
#else
#define MAYBE_ContentScriptIsolatedWorlds ContentScriptIsolatedWorlds
#endif
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, MAYBE_ContentScriptIsolatedWorlds) {
  // This extension runs various bits of script and tests that they all run in
  // the same isolated world.
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/isolated_world1")) << message_;

  // Now load a different extension, inject into same page, verify worlds aren't
  // shared.
  ASSERT_TRUE(RunExtensionTest("content_scripts/isolated_world2")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptIgnoreHostPermissions) {
  host_resolver()->AddRule("a.com", "127.0.0.1");
  host_resolver()->AddRule("b.com", "127.0.0.1");
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest(
      "content_scripts/dont_match_host_permissions")) << message_;
}

// crbug.com/39249 -- content scripts js should not run on view source.
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptViewSource) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/view_source")) << message_;
}

// crbug.com/126257 -- content scripts should not get injected into other
// extensions.
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptOtherExtensions) {
  host_resolver()->AddRule("a.com", "127.0.0.1");
  ASSERT_TRUE(StartEmbeddedTestServer());
  // First, load extension that sets up content script.
  ASSERT_TRUE(RunExtensionTest("content_scripts/other_extensions/injector"))
      << message_;
  // Then load targeted extension to make sure its content isn't changed.
  ASSERT_TRUE(RunExtensionTest("content_scripts/other_extensions/victim"))
      << message_;
}

class ContentScriptCssInjectionTest : public ExtensionApiTest {
 protected:
  // TODO(rdevlin.cronin): Make a testing switch that looks like FeatureSwitch,
  // but takes in an optional value so that we don't have to do this.
  void SetUpCommandLine(base::CommandLine* command_line) override {
    ExtensionApiTest::SetUpCommandLine(command_line);
    // We change the Webstore URL to be http://cws.com. We need to do this so
    // we can check that css injection is not allowed on the webstore (which
    // could lead to spoofing). Unfortunately, host_resolver seems to have
    // problems with redirecting "chrome.google.com" to the test server, so we
    // can't use the real Webstore's URL. If this changes, we could clean this
    // up.
    command_line->AppendSwitchASCII(
        switches::kAppsGalleryURL,
        base::StringPrintf("http://%s", kWebstoreDomain));
  }
};

IN_PROC_BROWSER_TEST_F(ContentScriptCssInjectionTest,
                       ContentScriptInjectsStyles) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  host_resolver()->AddRule(kWebstoreDomain, "127.0.0.1");

  ASSERT_TRUE(LoadExtension(test_data_dir_.AppendASCII("content_scripts")
                                          .AppendASCII("css_injection")));

  // CSS injection should be allowed on an aribitrary web page.
  GURL url =
      embedded_test_server()->GetURL("/extensions/test_file_with_body.html");
  EXPECT_TRUE(CheckStyleInjection(browser(), url, true));

  // The loaded extension has an exclude match for "extensions/test_file.html",
  // so no CSS should be injected.
  url = embedded_test_server()->GetURL("/extensions/test_file.html");
  EXPECT_TRUE(CheckStyleInjection(browser(), url, false));

  // We disallow all injection on the webstore.
  GURL::Replacements replacements;
  replacements.SetHostStr(kWebstoreDomain);
  url = embedded_test_server()->GetURL("/extensions/test_file_with_body.html")
            .ReplaceComponents(replacements);
  EXPECT_TRUE(CheckStyleInjection(browser(), url, false));
}

// crbug.com/120762
IN_PROC_BROWSER_TEST_F(
    ExtensionApiTest,
    DISABLED_ContentScriptStylesInjectedIntoExistingRenderers) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  content::WindowedNotificationObserver signal(
      extensions::NOTIFICATION_USER_SCRIPTS_UPDATED,
      content::Source<Profile>(browser()->profile()));

  // Start with a renderer already open at a URL.
  GURL url(embedded_test_server()->GetURL("/extensions/test_file.html"));
  ui_test_utils::NavigateToURL(browser(), url);

  LoadExtension(
      test_data_dir_.AppendASCII("content_scripts/existing_renderers"));

  signal.Wait();

  // And check that its styles were affected by the styles that just got loaded.
  bool styles_injected;
  ASSERT_TRUE(content::ExecuteScriptAndExtractBool(
      browser()->tab_strip_model()->GetActiveWebContents(),
      "window.domAutomationController.send("
      "    document.defaultView.getComputedStyle(document.body, null)."
      "        getPropertyValue('background-color') == 'rgb(255, 0, 0)')",
      &styles_injected));
  ASSERT_TRUE(styles_injected);
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest,
                       ContentScriptCSSLocalization) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/css_l10n")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptExtensionAPIs) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  const extensions::Extension* extension = LoadExtension(
      test_data_dir_.AppendASCII("content_scripts/extension_api"));

  ResultCatcher catcher;
  ui_test_utils::NavigateToURL(
      browser(),
      embedded_test_server()->GetURL(
          "/extensions/api_test/content_scripts/extension_api/functions.html"));
  EXPECT_TRUE(catcher.GetNextResult());

  // Navigate to a page that will cause a content script to run that starts
  // listening for an extension event.
  ui_test_utils::NavigateToURL(
      browser(),
      embedded_test_server()->GetURL(
          "/extensions/api_test/content_scripts/extension_api/events.html"));

  // Navigate to an extension page that will fire the event events.js is
  // listening for.
  ui_test_utils::NavigateToURLWithDisposition(
      browser(), extension->GetResourceURL("fire_event.html"),
      WindowOpenDisposition::NEW_FOREGROUND_TAB,
      ui_test_utils::BROWSER_TEST_NONE);
  EXPECT_TRUE(catcher.GetNextResult());
}

// Flaky on Windows. http://crbug.com/248418
#if defined(OS_WIN)
#define MAYBE_ContentScriptPermissionsApi DISABLED_ContentScriptPermissionsApi
#else
#define MAYBE_ContentScriptPermissionsApi ContentScriptPermissionsApi
#endif
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, MAYBE_ContentScriptPermissionsApi) {
  extensions::PermissionsRequestFunction::SetIgnoreUserGestureForTests(true);
  extensions::PermissionsRequestFunction::SetAutoConfirmForTests(true);
  host_resolver()->AddRule("*.com", "127.0.0.1");
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/permissions")) << message_;
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptBypassPageCSP) {
  ASSERT_TRUE(StartEmbeddedTestServer());
  ASSERT_TRUE(RunExtensionTest("content_scripts/bypass_page_csp")) << message_;
}

// Test that when injecting a blocking content script, other scripts don't run
// until the blocking script finishes.
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptBlockingScript) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  // Load up two extensions.
  TestExtensionDir ext_dir1;
  ext_dir1.WriteManifest(
      base::StringPrintf(kManifest, "ext1", "document_start"));
  ext_dir1.WriteFile(FILE_PATH_LITERAL("script.js"), kBlockingScript);
  const Extension* ext1 = LoadExtension(ext_dir1.unpacked_path());
  ASSERT_TRUE(ext1);

  TestExtensionDir ext_dir2;
  ext_dir2.WriteManifest(base::StringPrintf(kManifest, "ext2", "document_end"));
  ext_dir2.WriteFile(FILE_PATH_LITERAL("script.js"), kNonBlockingScript);
  const Extension* ext2 = LoadExtension(ext_dir2.unpacked_path());
  ASSERT_TRUE(ext2);

  content::WebContents* web_contents =
      browser()->tab_strip_model()->GetActiveWebContents();
  DialogHelper dialog_helper(web_contents);
  base::RunLoop run_loop;
  dialog_helper.set_quit_closure(run_loop.QuitClosure());

  ExtensionTestMessageListener listener("done", false);
  listener.set_extension_id(ext2->id());

  // Navigate! Both extensions will try to inject.
  ui_test_utils::NavigateToURLWithDisposition(
      browser(), embedded_test_server()->GetURL("/empty.html"),
      WindowOpenDisposition::CURRENT_TAB, ui_test_utils::BROWSER_TEST_NONE);

  run_loop.Run();
  // Right now, the alert dialog is showing and blocking injection of anything
  // after it, so the listener shouldn't be satisfied.
  EXPECT_FALSE(listener.was_satisfied());
  EXPECT_EQ(1u, dialog_helper.dialog_count());
  dialog_helper.CloseDialogs();

  // After closing the dialog, the rest of the scripts should be able to
  // inject.
  EXPECT_TRUE(listener.WaitUntilSatisfied());
}

// Test that closing a tab with a blocking script results in no further scripts
// running (and we don't crash).
IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptBlockingScriptTabClosed) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  // We're going to close a tab in this test, so make a new one (to ensure
  // we don't close the browser).
  ui_test_utils::NavigateToURLWithDisposition(
      browser(), embedded_test_server()->GetURL("/empty.html"),
      WindowOpenDisposition::NEW_FOREGROUND_TAB,
      ui_test_utils::BROWSER_TEST_WAIT_FOR_NAVIGATION);

  // Set up the same as the previous test case.
  TestExtensionDir ext_dir1;
  ext_dir1.WriteManifest(
      base::StringPrintf(kManifest, "ext1", "document_start"));
  ext_dir1.WriteFile(FILE_PATH_LITERAL("script.js"), kBlockingScript);
  const Extension* ext1 = LoadExtension(ext_dir1.unpacked_path());
  ASSERT_TRUE(ext1);

  TestExtensionDir ext_dir2;
  ext_dir2.WriteManifest(base::StringPrintf(kManifest, "ext2", "document_end"));
  ext_dir2.WriteFile(FILE_PATH_LITERAL("script.js"), kNonBlockingScript);
  const Extension* ext2 = LoadExtension(ext_dir2.unpacked_path());
  ASSERT_TRUE(ext2);

  content::WebContents* web_contents =
      browser()->tab_strip_model()->GetActiveWebContents();
  DialogHelper dialog_helper(web_contents);
  base::RunLoop run_loop;
  dialog_helper.set_quit_closure(run_loop.QuitClosure());

  ExtensionTestMessageListener listener("done", false);
  listener.set_extension_id(ext2->id());

  // Navitate!
  ui_test_utils::NavigateToURLWithDisposition(
      browser(), embedded_test_server()->GetURL("/empty.html"),
      WindowOpenDisposition::CURRENT_TAB, ui_test_utils::BROWSER_TEST_NONE);

  // Now, instead of closing the dialog, just close the tab. Later scripts
  // should never get a chance to run (and we shouldn't crash).
  run_loop.Run();
  EXPECT_FALSE(listener.was_satisfied());
  EXPECT_TRUE(browser()->tab_strip_model()->CloseWebContentsAt(
      browser()->tab_strip_model()->active_index(), 0));
  EXPECT_FALSE(listener.was_satisfied());
}

// There was a bug by which content scripts that blocked and ran on
// document_idle could be injected twice (crbug.com/431263). Test for
// regression.
IN_PROC_BROWSER_TEST_F(ExtensionApiTest,
                       ContentScriptBlockingScriptsDontRunTwice) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  // Load up an extension.
  TestExtensionDir ext_dir1;
  ext_dir1.WriteManifest(
      base::StringPrintf(kManifest, "ext1", "document_idle"));
  ext_dir1.WriteFile(FILE_PATH_LITERAL("script.js"), kBlockingScript);
  const Extension* ext1 = LoadExtension(ext_dir1.unpacked_path());
  ASSERT_TRUE(ext1);

  content::WebContents* web_contents =
      browser()->tab_strip_model()->GetActiveWebContents();
  DialogHelper dialog_helper(web_contents);
  base::RunLoop run_loop;
  dialog_helper.set_quit_closure(run_loop.QuitClosure());

  // Navigate!
  ui_test_utils::NavigateToURLWithDisposition(
      browser(), embedded_test_server()->GetURL("/empty.html"),
      WindowOpenDisposition::CURRENT_TAB, ui_test_utils::BROWSER_TEST_NONE);

  run_loop.Run();

  // The extension will have injected at idle, but it should only inject once.
  EXPECT_EQ(1u, dialog_helper.dialog_count());
  dialog_helper.CloseDialogs();
  EXPECT_TRUE(RunAllPending(web_contents));
  EXPECT_EQ(1u, dialog_helper.dialog_count());
}

// Bug fix for crbug.com/507461.
IN_PROC_BROWSER_TEST_F(ExtensionApiTest,
                       DocumentStartInjectionFromExtensionTabNavigation) {
  ASSERT_TRUE(StartEmbeddedTestServer());

  TestExtensionDir new_tab_override_dir;
  new_tab_override_dir.WriteManifest(kNewTabOverrideManifest);
  new_tab_override_dir.WriteFile(FILE_PATH_LITERAL("newtab.html"), kNewTabHtml);
  const Extension* new_tab_override =
      LoadExtension(new_tab_override_dir.unpacked_path());
  ASSERT_TRUE(new_tab_override);

  TestExtensionDir injector_dir;
  injector_dir.WriteManifest(
      base::StringPrintf(kManifest, "injector", "document_start"));
  injector_dir.WriteFile(FILE_PATH_LITERAL("script.js"), kNonBlockingScript);
  const Extension* injector = LoadExtension(injector_dir.unpacked_path());
  ASSERT_TRUE(injector);

  ExtensionTestMessageListener listener("done", false);
  AddTabAtIndex(0, GURL("chrome://newtab"), ui::PAGE_TRANSITION_LINK);
  browser()->tab_strip_model()->ActivateTabAt(0, false);
  content::WebContents* tab_contents =
      browser()->tab_strip_model()->GetActiveWebContents();

  EXPECT_EQ(new_tab_override->GetResourceURL("newtab.html"),
            tab_contents->GetMainFrame()->GetLastCommittedURL());
  EXPECT_FALSE(listener.was_satisfied());
  listener.Reset();

  ui_test_utils::NavigateToURLWithDisposition(
      browser(), embedded_test_server()->GetURL("/empty.html"),
      WindowOpenDisposition::CURRENT_TAB,
      ui_test_utils::BROWSER_TEST_WAIT_FOR_NAVIGATION);
  base::RunLoop().RunUntilIdle();
  EXPECT_TRUE(listener.was_satisfied());
}

IN_PROC_BROWSER_TEST_F(ExtensionApiTest,
                       DontInjectContentScriptsInBackgroundPages) {
  host_resolver()->AddRule("a.com", "127.0.0.1");
  ASSERT_TRUE(StartEmbeddedTestServer());
  // Load two extensions, one with an iframe to a.com in its background page,
  // the other, a content script for a.com. The latter should never be able to
  // inject the script, because scripts aren't allowed to run on foreign
  // extensions' pages.
  base::FilePath data_dir = test_data_dir_.AppendASCII("content_scripts");
  ExtensionTestMessageListener iframe_loaded_listener("iframe loaded", false);
  ExtensionTestMessageListener content_script_listener("script injected",
                                                       false);
  LoadExtension(data_dir.AppendASCII("script_a_com"));
  LoadExtension(data_dir.AppendASCII("background_page_iframe"));
  iframe_loaded_listener.WaitUntilSatisfied();
  EXPECT_FALSE(content_script_listener.was_satisfied());
}

}  // namespace extensions