Reset TaskScheduler during PepperToVideoTrackAdapterTest tear down.

content/renderer/media/pepper_to_video_track_adapter_unittest.cc

Index: content/renderer/media/pepper_to_video_track_adapter_unittest.cc
diff --git a/content/renderer/media/pepper_to_video_track_adapter_unittest.cc b/content/renderer/media/pepper_to_video_track_adapter_unittest.cc
index da0d50cb975978cd2d78defb998acfc08d166e76..073f1aebe882deb38b100754a1dd12e2a04e3fb6 100644
--- a/content/renderer/media/pepper_to_video_track_adapter_unittest.cc
+++ b/content/renderer/media/pepper_to_video_track_adapter_unittest.cc
@@ -2,9 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <memory>
 #include <string>
 
+#include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
+#include "base/task_scheduler/task_scheduler.h"
 #include "content/child/child_process.h"
 #include "content/public/test/mock_render_thread.h"
 #include "content/renderer/media/media_stream.h"
@@ -42,14 +45,22 @@ class PepperToVideoTrackAdapterTest : public PpapiUnittest {
     registry_.reset();
     blink::WebHeap::collectAllGarbageForTesting();
     PpapiUnittest::TearDown();
+
+    child_process_.reset();
+
+    // Clear the TaskScheduler registered by the ChildProcess. ChildProcess does
+    // not clear the TaskScheduler itself because CONTINUE_ON_SHUTDOWN tasks are
+    // allowed to outlive it.
+    base::TaskScheduler::GetInstance()->JoinForTesting();
+    base::TaskScheduler::SetInstance(nullptr);
   }
 
  protected:
-  // A ChildProcess and a MessageLoop are both needed to fool the Tracks and
-  // Sources inside |registry_| into believing they are on the right threads.
-  const ChildProcess child_process_;
-  const MockRenderThread render_thread_;
   std::unique_ptr<MockMediaStreamRegistry> registry_;
+
+  // A ChildProcess is needed by content::PepperToVideoTrackAdapter::Open.
+  std::unique_ptr<ChildProcess> child_process_ =
+      base::MakeUnique<ChildProcess>();
 };
 
 TEST_F(PepperToVideoTrackAdapterTest, Open) {
@@ -64,6 +75,7 @@ TEST_F(PepperToVideoTrackAdapterTest, Open) {
 }
 
 TEST_F(PepperToVideoTrackAdapterTest, PutFrame) {
+  MockRenderThread render_thread;
   FrameWriterInterface* frame_writer = NULL;
   EXPECT_TRUE(PepperToVideoTrackAdapter::Open(registry_.get(),
                                             kTestStreamUrl, &frame_writer));