Support exposing Mojo services between render frames, render threads, and their respective hosts.

content/public/renderer/render_frame.h

Index: content/public/renderer/render_frame.h
diff --git a/content/public/renderer/render_frame.h b/content/public/renderer/render_frame.h
index c48acd801239e3396a743c76ae11248e2c28a93e..cbc1546bd582b2e598b23be5ad1d6c8aac96fb66 100644
--- a/content/public/renderer/render_frame.h
+++ b/content/public/renderer/render_frame.h
@@ -25,6 +25,7 @@ struct WebPluginParams;
 namespace content {
 class ContextMenuClient;
 class RenderView;
+class ServiceRegistry;
 struct ContextMenuParams;
 struct WebPluginInfo;
 
@@ -88,6 +89,9 @@ class CONTENT_EXPORT RenderFrame : public IPC::Listener,
   // Return true if this frame is hidden.
   virtual bool IsHidden() = 0;
 
+  // Returns the ServiceRegistry for this frame.
+  virtual ServiceRegistry* GetServiceRegistry() = 0;
+
  protected:
   virtual ~RenderFrame() {}