Adds plumbing to pass WebUI mojo::Handle from browser to renderer

content/public/browser/render_view_host.h

Index: content/public/browser/render_view_host.h
diff --git a/content/public/browser/render_view_host.h b/content/public/browser/render_view_host.h
index 5f172fede7b14c4466911b98b55f9a41a48caff8..deab20c8708f5cbf84abed7356188109e2633b54 100644
--- a/content/public/browser/render_view_host.h
+++ b/content/public/browser/render_view_host.h
@@ -14,6 +14,10 @@
 #include "content/public/common/page_zoom.h"
 #include "third_party/WebKit/public/web/WebDragOperation.h"
 
+#if defined(USE_MOJO)
+#include "mojo/public/system/core_cpp.h"
+#endif
+
 class GURL;
 struct WebPreferences;
 
@@ -248,6 +252,11 @@ class CONTENT_EXPORT RenderViewHost : virtual public RenderWidgetHost {
   virtual void DisableFullscreenEncryptedMediaPlayback() = 0;
 #endif
 
+#if defined(USE_MOJO)
+  // Sets the mojo handle for WebUI pages.
+  virtual void SetWebUIHandle(mojo::ScopedMessagePipeHandle handle) = 0;
+#endif
+
  private:
   // This interface should only be implemented inside content.
   friend class RenderViewHostImpl;