Update from chromium https://crrev.com/301725/

base/run_loop.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 "base/run_loop.h"
 
 #include "base/bind.h"
 #include "base/tracked_objects.h"
 
 #if defined(OS_WIN)
@@ skipping 33 matching lines @@
 RunLoop::~RunLoop() {
 }
 
 void RunLoop::Run() {
   if (!BeforeRun())
     return;
 
   // Use task stopwatch to exclude the loop run time from the current task, if
   // any.
   tracked_objects::TaskStopwatch stopwatch;
+  stopwatch.Start();
   loop_->RunHandler();
   stopwatch.Stop();
 
   AfterRun();
 }
 
 void RunLoop::RunUntilIdle() {
   quit_when_idle_received_ = true;
   Run();
 }
@@ skipping 32 matching lines @@
 
   // Pop RunLoop stack:
   loop_->run_loop_ = previous_run_loop_;
 
   // Execute deferred QuitNow, if any:
   if (previous_run_loop_ && previous_run_loop_->quit_called_)
     loop_->QuitNow();
 }
 
 }  // namespace base