Revert of Verify if GPU message pump is signaled when it hangs in WaitForWork

base/message_loop/message_loop.h

 // Copyright 2013 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 BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_
 #define BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_
 
 #include <memory>
 #include <queue>
 #include <string>
@@ skipping 372 matching lines @@
   // Returns true if the message loop is "idle". Provided for testing.
   bool IsIdleForTesting();
 
   // Returns the TaskAnnotator which is used to add debug information to posted
   // tasks.
   debug::TaskAnnotator* task_annotator() { return &task_annotator_; }
 
   // Runs the specified PendingTask.
   void RunTask(const PendingTask& pending_task);
 
-#if defined(OS_WIN)
-  // TODO (stanisc): crbug.com/596190: Remove this after the signaling issue
-  // has been investigated.
-  // This should be used for diagnostic only. If message pump wake-up mechanism
-  // is based on auto-reset event this call would reset the event to unset
-  // state.
-  bool MessagePumpWasSignaled();
-#endif
-
   //----------------------------------------------------------------------------
  protected:
   std::unique_ptr<MessagePump> pump_;
 
   using MessagePumpFactoryCallback = Callback<std::unique_ptr<MessagePump>()>;
 
   // Common protected constructor. Other constructors delegate the
   // initialization to this constructor.
   // A subclass can invoke this constructor to create a message_loop of a
   // specific type with a custom loop. The implementation does not call
@@ skipping 278 matching lines @@
 
 // Do not add any member variables to MessageLoopForIO!  This is important b/c
 // MessageLoopForIO is often allocated via MessageLoop(TYPE_IO).  Any extra
 // data that you need should be stored on the MessageLoop's pump_ instance.
 static_assert(sizeof(MessageLoop) == sizeof(MessageLoopForIO),
               "MessageLoopForIO should not have extra member variables");
 
 }  // namespace base
 
 #endif  // BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_