Add RenderFrameHostDelegate and plumb it through all the necessary classes.

content/browser/frame_host/render_frame_host_delegate.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
+#define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
+
+namespace content {
+
+// An interface implemented by an object interested in knowing about the state
+// of the RenderFrameHost.
+class RenderFrameHostDelegate {
+ public:
+
+ protected:
+  virtual ~RenderFrameHostDelegate() {}
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_