Add a hang monitor for Pepper plugins

content/browser/ppapi_plugin_process_host.h

 // Copyright (c) 2011 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_PPAPI_PLUGIN_PROCESS_HOST_H_
 #define CONTENT_BROWSER_PPAPI_PLUGIN_PROCESS_HOST_H_
 #pragma once
 
 #include <queue>
 
@@ skipping 24 matching lines @@
  public:
   class Client {
    public:
     // Gets the information about the renderer that's requesting the channel.
     virtual void GetPpapiChannelInfo(base::ProcessHandle* renderer_handle,
                                      int* renderer_id) = 0;
 
     // Called when the channel is asynchronously opened to the plugin or on
     // error. On error, the parameters should be:
     //   base::kNullProcessHandle
-    //   IPC::ChannelHandle()
+    //   IPC::ChannelHandle(),
+    //   0
     virtual void OnPpapiChannelOpened(
         base::ProcessHandle plugin_process_handle,
-        const IPC::ChannelHandle& channel_handle) = 0;
+        const IPC::ChannelHandle& channel_handle,
+        int plugin_child_id) = 0;
   };
 
   class PluginClient : public Client {
    public:
     // Returns the resource context for the renderer requesting the channel.
     virtual content::ResourceContext* GetResourceContext() = 0;
   };
 
   class BrokerClient : public Client {
   };
@@ skipping 54 matching lines @@
 
   // Channel requests that we have already sent to the plugin process, but
   // haven't heard back about yet.
   std::queue<Client*> sent_requests_;
 
   // Path to the plugin library.
   FilePath plugin_path_;
 
   const bool is_broker_;
 
-  // The unique id created for the process.
-  int process_id_;
-
   scoped_ptr<BrowserChildProcessHostImpl> process_;
 
   DISALLOW_COPY_AND_ASSIGN(PpapiPluginProcessHost);
 };
 
 class PpapiPluginProcessHostIterator
     : public content::BrowserChildProcessHostTypeIterator<
           PpapiPluginProcessHost> {
  public:
   PpapiPluginProcessHostIterator()
       : content::BrowserChildProcessHostTypeIterator<
           PpapiPluginProcessHost>(content::PROCESS_TYPE_PPAPI_PLUGIN) {}
 };
 
 class PpapiBrokerProcessHostIterator
     : public content::BrowserChildProcessHostTypeIterator<
           PpapiPluginProcessHost> {
  public:
   PpapiBrokerProcessHostIterator()
       : content::BrowserChildProcessHostTypeIterator<
           PpapiPluginProcessHost>(content::PROCESS_TYPE_PPAPI_BROKER) {}
 };
 
 #endif  // CONTENT_BROWSER_PPAPI_PLUGIN_PROCESS_HOST_H_