Avoid scheduling a message loop that we know is not sleeping

base/message_loop/message_loop.cc

 // 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.
 
 #include "base/message_loop/message_loop.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 68 matching lines @@
   VALUE_TO_NUMBER_AND_NAME(kTimerEvent)
 
   {-1, NULL}  // The list must be null terminated, per API to histogram.
 };
 #endif  // !defined(OS_NACL)
 
 bool enable_histogrammer_ = false;
 
 MessageLoop::MessagePumpFactory* message_pump_for_ui_factory_ = NULL;
 
-// Returns true if MessagePump::ScheduleWork() must be called one
-// time for every task that is added to the MessageLoop incoming queue.
-bool AlwaysNotifyPump(MessageLoop::Type type) {
-#if defined(OS_ANDROID)
-  // The Android UI message loop needs to get notified each time a task is added
-  // to the incoming queue.
-  return type == MessageLoop::TYPE_UI || type == MessageLoop::TYPE_JAVA;
-#else
-  return false;
-#endif
-}
-
 #if defined(OS_IOS)
 typedef MessagePumpIOSForIO MessagePumpForIO;
 #elif defined(OS_NACL)
 typedef MessagePumpDefault MessagePumpForIO;
 #elif defined(OS_POSIX)
 typedef MessagePumpLibevent MessagePumpForIO;
 #endif
 
 MessagePumpForIO* ToPumpIO(MessagePump* pump) {
   return static_cast<MessagePumpForIO*>(pump);
@@ skipping 392 matching lines @@
   // We can improve performance of our loading tasks from the incoming queue to
   // |*work_queue| by waiting until the last minute (|*work_queue| is empty) to
   // load. That reduces the number of locks-per-task significantly when our
   // queues get large.
   if (work_queue_.empty()) {
     pending_high_res_tasks_ +=
         incoming_task_queue_->ReloadWorkQueue(&work_queue_);
   }
 }
 
-void MessageLoop::ScheduleWork(bool was_empty) {
-  if (was_empty || AlwaysNotifyPump(type_))
-    pump_->ScheduleWork();
+void MessageLoop::ScheduleWork() {
+  pump_->ScheduleWork();
 }
 
 //------------------------------------------------------------------------------
 // Method and data for histogramming events and actions taken by each instance
 // on each thread.
 
 void MessageLoop::StartHistogrammer() {
 #if !defined(OS_NACL)  // NaCl build has no metrics code.
   if (enable_histogrammer_ && !message_histogram_
       && StatisticsRecorder::IsActive()) {
@@ skipping 184 matching lines @@
       persistent,
       mode,
       controller,
       delegate);
 }
 #endif
 
 #endif  // !defined(OS_NACL)
 
 }  // namespace base