Chromecast: provides ExternalVideoSurfaceContainer for Android.
Since Chromecast on Android plays protected content and does so within
the bounds of the page (i.e. not launching the player full-screen over
the top of page content, as Clank does in this case), an
ExternalVideoSurfaceContainer is needed to provide a hardware-backed
video surface.
For the time being, the only implementation of this API has been
android_webview. This CL intends to use their existing code as a
starting point.
R=lcwu@chromium.org,byungchul@chromium.org,ycheo@chromium.org,qinmin@chromium.org
BUG=400876
Review URL: https://codereview.chromium.org/
607793002
Cr-Commit-Position: refs/heads/master@{#298002}