Add base::RunLoop and update ui_test_utils to use it to reduce flakiness

base/message_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/message_loop.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 295 matching lines @@
   AutoRunState save_state(this);
   RunHandler();
 }
 
 void MessageLoop::RunAllPending() {
   AutoRunState save_state(this);
   state_->quit_received = true;  // Means run until we would otherwise block.
   RunHandler();
 }
 
-void MessageLoop::Quit() {
+void MessageLoop::QuitWhenIdle() {
   DCHECK_EQ(this, current());
   if (state_) {
     state_->quit_received = true;
   } else {
     NOTREACHED() << "Must be inside Run to call Quit";
   }
 }
 
 void MessageLoop::QuitNow() {
   DCHECK_EQ(this, current());
   if (state_) {
     pump_->Quit();
   } else {
     NOTREACHED() << "Must be inside Run to call Quit";
   }
 }
 
-static void QuitCurrent() {
-  MessageLoop::current()->Quit();
+void MessageLoop::QuitAfterPending() {
+  DCHECK_EQ(this, current());
+  if (state_) {
+    PostTask(FROM_HERE, MessageLoop::QuitNowClosure());
+  } else {
+    NOTREACHED() << "Must be inside Run to call Quit";
+  }
+}
+
+static void QuitWhenIdleCurrent() {
+  MessageLoop::current()->QuitWhenIdle();
+}
+
+static void QuitNowCurrent() {
+  MessageLoop::current()->QuitNow();
+}
+
+static void QuitAfterPendingCurrent() {
+  MessageLoop::current()->QuitAfterPending();
 }
 
 // static
-base::Closure MessageLoop::QuitClosure() {
-  return base::Bind(&QuitCurrent);
+base::Closure MessageLoop::QuitWhenIdleClosure() {
+  return base::Bind(&QuitWhenIdleCurrent);
+}
+
+// static
+base::Closure MessageLoop::QuitNowClosure() {
+  return base::Bind(&QuitNowCurrent);
+}
+
+// static
+base::Closure MessageLoop::QuitAfterPendingClosure() {
+  return base::Bind(&QuitAfterPendingCurrent);
 }
 
 void MessageLoop::SetNestableTasksAllowed(bool allowed) {
   if (nestable_tasks_allowed_ != allowed) {
     nestable_tasks_allowed_ = allowed;
     if (!nestable_tasks_allowed_)
       return;
     // Start the native pump if we are not already pumping.
     pump_->ScheduleWork();
   }
@@ skipping 450 matching lines @@
                                            Watcher *delegate) {
   return pump_libevent()->WatchFileDescriptor(
       fd,
       persistent,
       static_cast<base::MessagePumpLibevent::Mode>(mode),
       controller,
       delegate);
 }
 
 #endif