content: convert child process notifications to observer usage

content/browser/browser_child_process_host_impl.h

 // Copyright (c) 2012 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_BROWSER_CHILD_PROCESS_HOST_IMPL_H_
 #define CONTENT_BROWSER_BROWSER_CHILD_PROCESS_HOST_IMPL_H_
 
 #include <list>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/process.h"
 #include "content/browser/child_process_launcher.h"
 #include "content/public/browser/browser_child_process_host.h"
 #include "content/public/browser/child_process_data.h"
 #include "content/public/common/child_process_host_delegate.h"
 
 namespace content {
+
 class BrowserChildProcessHostIterator;
+class BrowserChildProcessObserver;
 
 // Plugins/workers and other child processes that live on the IO thread use this
 // class. RenderProcessHostImpl is the main exception that doesn't use this
 /// class because it lives on the UI thread.
 class CONTENT_EXPORT BrowserChildProcessHostImpl
     : public BrowserChildProcessHost,
       public NON_EXPORTED_BASE(ChildProcessHostDelegate),
       public ChildProcessLauncher::Client {
  public:
   BrowserChildProcessHostImpl(
@@ skipping 25 matching lines @@
   // OnProcessLaunched is called or it will be invalid and may crash.
   base::ProcessHandle GetHandle() const;
 
   // Removes this host from the host list. Calls ChildProcessHost::ForceShutdown
   void ForceShutdown();
 
   // Controls whether the child process should be terminated on browser
   // shutdown. Default is to always terminate.
   void SetTerminateChildOnShutdown(bool terminate_on_shutdown);
 
-  // Sends the given notification on the UI thread.
-  void Notify(int type);
+  // Called when an instance of a particular child is created in a page.
+  static void NotifyProcessInstanceCreated(const ChildProcessData& data);
 
-  BrowserChildProcessHostDelegate* delegate() const { return delegate_;
-  }
+  BrowserChildProcessHostDelegate* delegate() const { return delegate_; }
 
   typedef std::list<BrowserChildProcessHostImpl*> BrowserChildProcessList;
  private:
   friend class BrowserChildProcessHostIterator;
+  friend class BrowserChildProcessObserver;
 
   static BrowserChildProcessList* GetIterator();
 
+  static void AddObserver(BrowserChildProcessObserver* observer);
+  static void RemoveObserver(BrowserChildProcessObserver* observer);
+
   // ChildProcessHostDelegate implementation:
   virtual bool CanShutdown() OVERRIDE;
   virtual void OnChildDisconnected() OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   virtual void OnChannelConnected(int32 peer_pid) OVERRIDE;
   virtual void OnChannelError() OVERRIDE;
 
   // ChildProcessLauncher::Client implementation.
   virtual void OnProcessLaunched() OVERRIDE;
 
   ChildProcessData data_;
   BrowserChildProcessHostDelegate* delegate_;
   scoped_ptr<ChildProcessHost> child_process_host_;
 
   scoped_ptr<ChildProcessLauncher> child_process_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BROWSER_CHILD_PROCESS_HOST_IMPL_H_