Add a RenderProcessObserver. For now this will be primarily used to filter control messages, so ...

chrome/renderer/render_thread.h

 // Copyright (c) 2010 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 CHROME_RENDERER_RENDER_THREAD_H_
 #define CHROME_RENDERER_RENDER_THREAD_H_
 #pragma once
 
+#include <list>
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/shared_memory.h"
 #include "base/time.h"
 #include "base/timer.h"
 #include "build/build_config.h"
 #include "chrome/common/extensions/extension_set.h"
 #include "chrome/renderer/chrome_content_renderer_client.h"
 #include "chrome/renderer/visitedlink_slave.h"
 #include "content/common/child_thread.h"
 #include "content/common/css_colors.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "ipc/ipc_platform_file.h"
 #include "ui/gfx/native_widget_types.h"
 
 class AppCacheDispatcher;
 class CookieMessageFilter;
 class DBMessageFilter;
 class DevToolsAgentFilter;
 class ExtensionSet;
 class FilePath;
 class GpuChannelHost;
 class IndexedDBDispatcher;
 class ListValue;
 class RendererHistogram;
 class RendererHistogramSnapshots;
+class RenderProcessObserver;
 class RendererNetPredictor;
 class RendererWebKitClientImpl;
 class SpellCheck;
 class SkBitmap;
 class UserScriptSlave;
 class URLPattern;
 class WebDatabaseObserverImpl;
 
 struct ContentSettings;
 struct RendererPreferences;
@@ skipping 359 matching lines @@
   // Map of registered v8 extensions. The key is the extension name. The value
   // is true if the extension should be restricted to extension-related
   // contexts.
   std::map<std::string, bool> v8_extensions_;
 
   // Contains all loaded extensions.
   ExtensionSet extensions_;
 
   chrome::ChromeContentRendererClient renderer_client_;
 
+  typedef std::list<RenderProcessObserver*> RenderProcessObserverList;
+  RenderProcessObserverList observers_;

[brettw, 2011/03/26 18:08:48]

I wonder if this should be a base::ObserverList in case one of the callbacks
starts modifying the list in a notification. If we're not worried about
modification, I'd just use a vector which should be less overhead than a list.

[jam, 2011/03/27 22:55:47]

I've switched to ObserverList just to be safe.

+
   DISALLOW_COPY_AND_ASSIGN(RenderThread);
 };
 
 #endif  // CHROME_RENDERER_RENDER_THREAD_H_