[chromecast] Pass media task runner to VideoPlaneController.

chromecast/app/cast_main_delegate.cc

Index: chromecast/app/cast_main_delegate.cc
diff --git a/chromecast/app/cast_main_delegate.cc b/chromecast/app/cast_main_delegate.cc
index 74601753440a9d1b4be6b13c31c4bdd69833f452..7ae36efa20a84311f44f7c04d5e0df8a509b98cf 100644
--- a/chromecast/app/cast_main_delegate.cc
+++ b/chromecast/app/cast_main_delegate.cc
@@ -165,11 +165,6 @@ int CastMainDelegate::RunProcess(
 #endif  // defined(OS_ANDROID)
 }
 
-void CastMainDelegate::ProcessExiting(const std::string& process_type) {
-  if (process_type.empty())
-    browser_client_->ProcessExiting();
-}
-
 #if !defined(OS_ANDROID)
 void CastMainDelegate::ZygoteForked() {
   const base::CommandLine* command_line(base::CommandLine::ForCurrentProcess());