Add flag that enable Encrypted Media Extensions on video elements.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 04bb0d9682437cf8179a73586da0d9dd94e857f4..6e0e1abd5ce7ac9a7dd76e55be11a366aaecc8cf 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -530,6 +530,9 @@ void RenderThreadImpl::EnsureWebKitInitialized() {
   WebKit::WebRuntimeFeatures::enableVideoTrack(
       command_line.HasSwitch(switches::kEnableVideoTrack));
 
+  WebKit::WebRuntimeFeatures::enableMediaEncrypted(
+      command_line.HasSwitch(switches::kEnableMediaEncrypted));
+
 #if defined(OS_CHROMEOS)
   // TODO(crogers): enable once Web Audio has been tested and optimized.
   WebRuntimeFeatures::enableWebAudio(false);