Remove usage of FOR_EACH_OBSERVER macro in gpu

gpu/ipc/service/gpu_command_buffer_stub.cc

 // 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.
 
 #include "gpu/ipc/service/gpu_command_buffer_stub.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 410 matching lines @@
   executor_.reset();
 
   sync_point_client_.reset();
 
   bool have_context = false;
   if (decoder_ && decoder_->GetGLContext()) {
     // Try to make the context current regardless of whether it was lost, so we
     // don't leak resources.
     have_context = decoder_->GetGLContext()->MakeCurrent(surface_.get());
   }
-  FOR_EACH_OBSERVER(DestructionObserver,
-                    destruction_observers_,
-                    OnWillDestroyStub());
+  for (auto& observer : destruction_observers_)
+    observer.OnWillDestroyStub();
 
   if (decoder_) {
     decoder_->Destroy(have_context);
     decoder_.reset();
   }
 
   command_buffer_.reset();
 
   // Remove this after crbug.com/248395 is sorted out.
   surface_ = NULL;
@@ skipping 670 matching lines @@
   Send(new GpuCommandBufferMsg_SwapBuffersCompleted(route_id_, params));
 }
 
 void GpuCommandBufferStub::SendUpdateVSyncParameters(base::TimeTicks timebase,
                                                      base::TimeDelta interval) {
   Send(new GpuCommandBufferMsg_UpdateVSyncParameters(route_id_, timebase,
                                                      interval));
 }
 
 }  // namespace gpu