Enable the embedded L1/EME support in WebView.

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 a172b86951137bfc34a6ebf2bb794d6ce2c32b66..8e0b8c25c0b92a9b8f42110d15947e6ff0b08f77 100644
--- a/android_webview/lib/main/aw_main_delegate.cc
+++ b/android_webview/lib/main/aw_main_delegate.cc
@@ -26,6 +26,7 @@
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/client/gl_in_process_context.h"
 #include "gpu/command_buffer/service/in_process_command_buffer.h"
+#include "media/base/media_switches.h"
 #include "webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.h"
 
 namespace android_webview {
@@ -81,6 +82,11 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
   // Disable WebRTC.
   cl->AppendSwitch(switches::kDisableWebRTC);
 
+#if defined(VIDEO_HOLE)
+  // Support EME/L1 with hole-punching.
+  cl->AppendSwitch(switches::kMediaDrmEnableNonCompositing);
+#endif
+
   return false;
 }