Teach the native viewport service to draw a Surface into itself

mojo/examples/pepper_container_app/pepper_container_app.cc

Index: mojo/examples/pepper_container_app/pepper_container_app.cc
diff --git a/mojo/examples/pepper_container_app/pepper_container_app.cc b/mojo/examples/pepper_container_app/pepper_container_app.cc
index 07e88515b68e3bd97bb11ac89b6d17a603076326..d8ba4e8fb3f6dee53ba6f5519f98967264deb785 100644
--- a/mojo/examples/pepper_container_app/pepper_container_app.cc
+++ b/mojo/examples/pepper_container_app/pepper_container_app.cc
@@ -94,6 +94,7 @@ class PepperContainerApp: public ApplicationDelegate,
     SizePtr size = Size::New();
     size->width = 800;
     size->width = 600;
+    // TODO(jamesr): Output a surface to the native viewport instead.
     gpu_service_->CreateOnscreenGLES2Context(
         native_viewport_id_, size.Pass(), Get(&command_buffer));
     return command_buffer.PassMessagePipe();