Handle context loss in WebMediaPlayerPlayer in-process

Add plumbing for a ResetStreamTextureProxy which should be
called on the event of a context loss. Only hooked up the
call for the in-process implementation in this CL when the
contex is restored.

ResetStreamTextureProxy currently handles "onContextLoss" as
well as "onContextRestored" concepts. It deletes the old
stream texture id, and recreates and binds a new
StreamTextureProxy.

BUG=412578

Review URL: https://codereview.chromium.org/532993002

Cr-Commit-Position: refs/heads/master@{#295219}
9 files changed