Create RenderFrameProxyHost at time of swap-out instead of commit.

content/renderer/render_frame_proxy.h

+// Copyright 2014 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_RENDERER_RENDER_FRAME_PROXY_H_
+#define CONTENT_RENDERER_RENDER_FRAME_PROXY_H_
+
+#include "base/basictypes.h"
+#include "content/common/content_export.h"
+#include "ipc/ipc_listener.h"
+#include "ipc/ipc_sender.h"
+
+#include "third_party/WebKit/public/web/WebFrameClient.h"
+#include "third_party/WebKit/public/web/WebRemoteFrame.h"
+
+namespace content {
+
+class RenderFrameImpl;
+class RenderViewImpl;
+
+// When a page's frames are rendered by multiple processes, each renderer has a
+// full copy of the frame tree. It has full RenderFrames for the frames it is
+// responsible for rendering and placeholder objects for frames rendered by
+// other processes. This class is the renderer-side object for the placeholder.
+// RenderFrameProxy allows us to keep existing window references valid over
+// cross-process navigations and route cross-site asynchronous JavaScript calls,
+// such as postMessage.
+//
+// For now, RenderFrameProxy is created when RenderFrame is swapped out. It
+// acts as a wrapper and is used for sending and receiving IPC messages. It is
+// deleted when the RenderFrame is swapped back in or the node of the frame
+// tree is deleted.
+//
+// Long term, RenderFrameProxy will be created to replace the RenderFrame in the
+// frame tree and the RenderFrame will be deleted after its unload handler has
+// finished executing. It will still be responsible for routing IPC messages
+// which are valid for cross-site interactions between frames.
+// RenderFrameProxy will be deleted when the node in the frame tree is deleted
+// or when navigating the frame causes it to return to this process and a new
+// RenderFrame is created for it.
+class CONTENT_EXPORT RenderFrameProxy
+    : public IPC::Listener,
+      public IPC::Sender,
+      NON_EXPORTED_BASE(public blink::WebFrameClient) {
+ public:
+  static RenderFrameProxy* CreateFrameProxy(int routing_id,
+                                            int frame_routing_id);
+
+  // Returns the RenderFrameProxy for the given routing ID.
+  static RenderFrameProxy* FromRoutingID(int routing_id);
+
+  virtual ~RenderFrameProxy();
+
+  // IPC::Sender
+  virtual bool Send(IPC::Message* msg) OVERRIDE;
+
+  RenderFrameImpl* render_frame() {
+    return render_frame_;
+  }
+
+ private:
+  RenderFrameProxy(int routing_id, int frame_routing_id);
+
+  // IPC::Listener
+  virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
+
+  // IPC handlers
+  void OnDeleteProxy();
+
+  int routing_id_;
+  int frame_routing_id_;
+  RenderFrameImpl* render_frame_;
+
+  DISALLOW_COPY_AND_ASSIGN(RenderFrameProxy);
+};
+
+}  // namespace
+
+#endif  // CONTENT_RENDERER_RENDER_FRAME_PROXY_H_