Fix leak reported by valgrind in VideoDestinationHandlerTest.PutFrame

content/renderer/media/webrtc/video_destination_handler_unittest.cc

 // Copyright (c) 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 <string>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/child/child_process.h"
@@ skipping 79 matching lines @@
                              PPB_ImageData_Impl::ForTest()));
   image->Init(PP_IMAGEDATAFORMAT_BGRA_PREMUL, 640, 360, true);
   {
     base::RunLoop run_loop;
     base::Closure quit_closure = run_loop.QuitClosure();
 
     EXPECT_CALL(sink, OnVideoFrame()).WillOnce(
         RunClosure(quit_closure));
     frame_writer.Run(image.get(), 10);
     run_loop.Run();
+    // Run all pending tasks to let the the test clean up before the test ends.
+    // This is due to that
+    // FrameWriterDelegate::FrameWriterDelegate::DeliverFrame use
+    // PostTaskAndReply to the IO thread and expects the reply to process
+    // on the main render thread to clean up its resources. However, the
+    // QuitClosure above ends before that.
+    base::MessageLoop::current()->RunUntilIdle();
   }
   EXPECT_EQ(1, sink.number_of_frames());
   native_track->RemoveSink(&sink);
 }
 
 }  // namespace content