Add support for multimedia timers to TaskQueue on Windows.

webrtc/base/task_queue_unittest.cc

 /*
  *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 94 matching lines @@
   // which is why we have a little bit of leeway backwards as well.
   EXPECT_GE(end - start, 90u);
   EXPECT_NEAR(end - start, 190u, 100u);  // Accept 90-290.
 }
 
 TEST(TaskQueueTest, PostMultipleDelayed) {
   static const char kQueueName[] = "PostMultipleDelayed";
   TaskQueue queue(kQueueName);
 
   std::vector<std::unique_ptr<Event>> events;
-  for (int i = 0; i < 10; ++i) {
+  for (int i = 0; i < 100; ++i) {
     events.push_back(std::unique_ptr<Event>(new Event(false, false)));
     queue.PostDelayedTask(
         Bind(&CheckCurrent, kQueueName, events.back().get(), &queue), 10);
   }
 
   for (const auto& e : events)
     EXPECT_TRUE(e->Wait(100));
 }
 
 TEST(TaskQueueTest, PostDelayedAfterDestruct) {
@@ skipping 126 matching lines @@
       queue.PostTask(NewClosure([&tasks_executed]() { ++tasks_executed; },
                                 [&tasks_cleaned_up]() { ++tasks_cleaned_up; }));
     event.Set();  // Unblock the first task.
   }
 
   EXPECT_GE(tasks_cleaned_up, tasks_executed);
   EXPECT_EQ(kTaskCount, tasks_cleaned_up);
 }
 
 }  // namespace rtc