media: Add GpuMojoMediaClient.

media/mojo/services/mojo_media_application_factory.cc

Index: media/mojo/services/mojo_media_application_factory.cc
diff --git a/media/mojo/services/mojo_media_application_factory.cc b/media/mojo/services/mojo_media_application_factory.cc
index 715cbc31f51f27bf7e376ea9ae2cb51a2ab63f6e..d2e7527f2e4ed3bb199619c526e143a4d891e107 100644
--- a/media/mojo/services/mojo_media_application_factory.cc
+++ b/media/mojo/services/mojo_media_application_factory.cc
@@ -19,6 +19,8 @@ namespace media {
 
 // static
 std::unique_ptr<shell::Service> CreateMojoMediaApplication(
+    scoped_refptr<base::SingleThreadTaskRunner> media_service_task_runner,
+    MediaService* media_service,

[xhwang, 2016/09/30 22:39:11]

This will make media/mojo depend on media/gpu which in turn depends on /gpu and
/ui. This makes me wonder whether you can provide your own function to create
MojoMediaApplication similar to what Cast is doing [2]?

[1] https://cs.chromium.org/chromium/src/media/gpu/BUILD.gn?rcl=0&l=181

[2]
https://cs.chromium.org/chromium/src/chromecast/browser/cast_content_browser_...

[sandersd (OOO until July 31), 2016/09/30 22:40:50]

Good point. In this case we can pass it as a raw pointer the whole way, and so
can get away with just forward declaration everywhere. Would that be considered
acceptable?

     const base::Closure& quit_closure) {
   return std::unique_ptr<shell::Service>(new MojoMediaApplication(
       base::MakeUnique<DefaultClient>(), quit_closure));