Revert of Revert of Forward input and compositing tasks to the Blink scheduler

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index ea65fd28a7230b852ea4de4881f2b02b6cfcf401..081404dc232526f2fbeb367e628d2d972894d1db 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -43,6 +43,7 @@
 
 namespace base {
 class MessageLoopProxy;
+class SingleThreadTaskRunner;
 class Thread;
 }
 
@@ -198,6 +199,11 @@
     return webkit_platform_support_.get();
   }
 
+  scoped_refptr<base::SingleThreadTaskRunner>
+  main_thread_compositor_task_runner() const {
+    return main_thread_compositor_task_runner_;
+  }
+
   IPC::ForwardingMessageFilter* compositor_output_surface_filter() const {
     return compositor_output_surface_filter_.get();
   }
@@ -567,6 +573,10 @@
 
   scoped_ptr<MemoryObserver> memory_observer_;
 
+  scoped_refptr<base::SingleThreadTaskRunner>
+      main_thread_compositor_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> main_thread_input_task_runner_;
+
   // Compositor settings
   bool is_gpu_rasterization_enabled_;
   bool is_gpu_rasterization_forced_;