Revert "Flip unified media pipeline to default-on w/ disabled holdback."

android_webview/lib/main/aw_main_delegate.cc

Index: android_webview/lib/main/aw_main_delegate.cc
diff --git a/android_webview/lib/main/aw_main_delegate.cc b/android_webview/lib/main/aw_main_delegate.cc
index f14d45d0b51e53a520bbf7643b9622e41169cf5b..0e2264acfd52f668caaab77c59d5acb6dc1c1099 100644
--- a/android_webview/lib/main/aw_main_delegate.cc
+++ b/android_webview/lib/main/aw_main_delegate.cc
@@ -140,10 +140,6 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
     cl->AppendSwitch(switches::kDisableRendererBackgrounding);
   }
 
-  // TODO(liberato, watk): Reenable after resolving fullscreen test failures.
-  // See http://crbug.com/597495
-  cl->AppendSwitch(switches::kDisableUnifiedMediaPipeline);
-
   return false;
 }