Revert of Improving the fake clock and using it to fix a flaky STUN timeout test.

webrtc/base/messagequeue.h

Index: webrtc/base/messagequeue.h
diff --git a/webrtc/base/messagequeue.h b/webrtc/base/messagequeue.h
index bf110376b58d7eb681fb93477d8ac02384c6365d..3a5226cd0a0129bb6c149b170922eef6123b3614 100644
--- a/webrtc/base/messagequeue.h
+++ b/webrtc/base/messagequeue.h
@@ -37,7 +37,7 @@
 
 // MessageQueueManager does cleanup of of message queues
 
-class MessageQueueManager {
+class MessageQueueManager : public MessageHandler {
  public:
   static void Add(MessageQueue *message_queue);
   static void Remove(MessageQueue *message_queue);
@@ -50,20 +50,21 @@
   static bool IsInitialized();
 
   // Mainly for testing purposes, for use with a simulated clock.
-  // Ensures that all message queues have processed delayed messages
-  // up until the current point in time.
-  static void ProcessAllMessageQueues();
+  // Posts a no-op event on all message queues so they will wake from the
+  // socket server select() and process messages again.
+  static void WakeAllMessageQueues();
 
  private:
   static MessageQueueManager* Instance();
 
   MessageQueueManager();
-  ~MessageQueueManager();
+  ~MessageQueueManager() override;
 
   void AddInternal(MessageQueue *message_queue);
   void RemoveInternal(MessageQueue *message_queue);
   void ClearInternal(MessageHandler *handler);
-  void ProcessAllMessageQueuesInternal();
+  void WakeAllMessageQueuesInternal();
+  void OnMessage(Message* pmsg) override;
 
   static MessageQueueManager* instance_;
   // This list contains all live MessageQueues.