Service CreateNewWindow on the UI thread with a new mojo interface

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 83960ac56a5609252c1fef93fd6d9e8026010b0c..87e3dfc4762074c516812cd4578255607e1ef685 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -170,6 +170,7 @@ class CONTENT_EXPORT RenderThreadImpl
       std::unique_ptr<blink::scheduler::RendererScheduler> renderer_scheduler);
   static RenderThreadImpl* current();
   static mojom::RenderMessageFilter* current_render_message_filter();
+  static mojom::RenderMessageFilterUI* current_render_message_filter_ui();
 
   static void SetRenderMessageFilterForTesting(
       mojom::RenderMessageFilter* render_message_filter);
@@ -366,6 +367,7 @@ class CONTENT_EXPORT RenderThreadImpl
   }
 
   mojom::RenderFrameMessageFilter* render_frame_message_filter();
+  mojom::RenderMessageFilterUI* render_message_filter_ui();
   mojom::RenderMessageFilter* render_message_filter();
 
   // Get the GPU channel. Returns NULL if the channel is not established or
@@ -776,6 +778,7 @@ class CONTENT_EXPORT RenderThreadImpl
 
   mojom::RenderFrameMessageFilterAssociatedPtr render_frame_message_filter_;
   mojom::RenderMessageFilterAssociatedPtr render_message_filter_;
+  mojom::RenderMessageFilterUIPtr render_message_filter_ui_ = nullptr;
 
   base::CancelableClosure record_purge_suspend_metric_closure_;
   RendererMemoryMetrics purge_and_suspend_memory_metrics_;