Implement FetchEvent.navigationPreload
This CL depends on https://codereview.chromium.org/2410333006/
FetchEvent.navigationPreload will be implemented in the following steps.
[1/4] Introduce FetchEventPreloadHandle to pass the preload response to FetchEvent.
https://codereview.chromium.org/2417793002/
[2/4] Implement ServiceWorkerFetchDispatcher::MaybeStartNavigationPreload().
https://codereview.chromium.org/2410333006/
[3/4] Implement FetchEvent.navigationPreload.
https://codereview.chromium.org/2416843002/ This CL.
[4/4] Add browser tests for NavigationPreload.
https://codereview.chromium.org/2413643005/
If ServiceWorkerContextClient::FetchEventDispatcherImpl receives preload_handle,
it creates a PreloadRequest. This PreloadRequest is a mojom::URLLoaderClient
owning mojom::URLLoader.
ServiceWorkerContextClient::DispatchFetchEvent() stores the PreloadRequest to
|context_| and calls ServiceWorkerGlobalScopeProxy::dispatchFetchEvent() with
|navigationPreloadSent| flag set.
If the flag is set, ServiceWorkerGlobalScopeProxy::dispatchFetchEvent() calls
FetchEvent::createPreloadResponseCallback() to create
WebServiceWorkerPreloadResponseCallbacks and calls registerPreloadResponseCallback
to pass the callback to ServiceWorkerContextClient.
ServiceWorkerContextClient::registerPreloadResponseCallback() calls
PreloadRequest::RegisterCallback() and the callback will be called when
OnStartLoadingResponseBody() is called or OnComplete() is called with an error.
BUG=649558
Review-Url: https://codereview.chromium.org/2416843002
Cr-Commit-Position: refs/heads/master@{#427303}
10 files changed
