Revert of Remove RenderFrameMessageFilter.

content/browser/frame_host/render_frame_message_filter.h

Index: content/browser/frame_host/render_frame_message_filter.h
diff --git a/content/browser/frame_host/render_frame_message_filter.h b/content/browser/frame_host/render_frame_message_filter.h
new file mode 100644
index 0000000000000000000000000000000000000000..e60343acbb7615fd4e89eec3e2d81bcd4fcf2f55
--- /dev/null
+++ b/content/browser/frame_host/render_frame_message_filter.h
@@ -0,0 +1,45 @@
+// 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_MESSAGE_FILTER_H_
+#define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_MESSAGE_FILTER_H_
+
+#include "content/common/frame_replication_state.h"
+#include "content/public/browser/browser_message_filter.h"
+#include "third_party/WebKit/public/web/WebTreeScopeType.h"
+
+namespace content {
+class RenderWidgetHelper;
+
+// RenderFrameMessageFilter intercepts FrameHost messages on the IO thread
+// that require low-latency processing. The canonical example of this is
+// child-frame creation which is a sync IPC that provides the renderer
+// with the routing id for a newly created RenderFrame.
+//
+// This object is created on the UI thread and used on the IO thread.
+class RenderFrameMessageFilter : public BrowserMessageFilter {
+ public:
+  RenderFrameMessageFilter(int render_process_id,
+                           RenderWidgetHelper* render_widget_helper);
+
+  bool OnMessageReceived(const IPC::Message& message) override;
+
+ private:
+  ~RenderFrameMessageFilter() override;
+
+  void OnCreateChildFrame(int parent_routing_id,
+                          blink::WebTreeScopeType scope,
+                          const std::string& frame_name,
+                          blink::WebSandboxFlags sandbox_flags,
+                          int* new_render_frame_id);
+
+  const int render_process_id_;
+
+  // Needed for issuing routing ids and surface ids.
+  scoped_refptr<RenderWidgetHelper> render_widget_helper_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_MESSAGE_FILTER_H_