Make IPC::Logging register to watch for message loop destruction.

chrome/common/ipc_logging.h

 // Copyright (c) 2006-2008 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_COMMON_IPC_LOGGING_H_
 #define CHROME_COMMON_IPC_LOGGING_H_
 
 #include "chrome/common/ipc_message.h"  // For IPC_MESSAGE_LOG_ENABLED.
 
 #ifdef IPC_MESSAGE_LOG_ENABLED
 
 #include "base/lock.h"
+#include "base/message_loop.h"
 #include "base/singleton.h"
 #include "base/waitable_event_watcher.h"
 #include "chrome/common/ipc_message_utils.h"
 
 class MessageLoop;
 
 namespace IPC {
 
 class Message;
 
 // One instance per process.  Needs to be created on the main thread (the UI
 // thread in the browser) but OnPreDispatchMessage/OnPostDispatchMessage
 // can be called on other threads.
-class Logging : public base::WaitableEventWatcher::Delegate {
+class Logging : public base::WaitableEventWatcher::Delegate,
+                public MessageLoop::DestructionObserver {
  public:
   // Implemented by consumers of log messages.
   class Consumer {
    public:
     virtual void Log(const LogData& data) = 0;
   };
 
   void SetConsumer(Consumer* consumer);
 
   ~Logging();
@@ skipping 23 matching lines @@
 
   // Like the *MsgLog functions declared for each message class, except this
   // calls the correct one based on the message type automatically.  Defined in
   // ipc_logging.cc.
   static void GetMessageText(uint16 type, std::wstring* name,
                              const Message* message, std::wstring* params);
 
   // WaitableEventWatcher::Delegate implementation
   void OnWaitableEventSignaled(base::WaitableEvent* event);
 
+  // MessageLoop::DestructionObserver implementation
+  void WillDestroyCurrentMessageLoop();
+
   typedef void (*LogFunction)(uint16 type,
                              std::wstring* name,
                              const Message* msg,
                              std::wstring* params);
 
   static void SetLoggerFunctions(LogFunction *functions);
 
  private:
   friend struct DefaultSingletonTraits<Logging>;
   Logging();
@@ skipping 20 matching lines @@
 
   static LogFunction *log_function_mapping_;
 };
 
 }  // namespace IPC
 
 #endif // IPC_MESSAGE_LOG_ENABLED
 
 #endif  // CHROME_COMMON_IPC_LOGGING_H_