Remove unused variables.

media/renderers/default_renderer_factory.cc

 // Copyright 2014 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 "media/renderers/default_renderer_factory.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
@@ skipping 54 matching lines @@
   return audio_decoders;
 }
 
 ScopedVector<VideoDecoder> DefaultRendererFactory::CreateVideoDecoders(
     const scoped_refptr<base::SingleThreadTaskRunner>& media_task_runner,
     const RequestSurfaceCB& request_surface_cb,
     GpuVideoAcceleratorFactories* gpu_factories) {
   // Create our video decoders and renderer.
   ScopedVector<VideoDecoder> video_decoders;
 
-  // |gpu_factories_| requires that its entry points be called on its
-  // |GetTaskRunner()|.  Since |pipeline_| will own decoders created from the
-  // factories, require that their message loops are identical.
-  DCHECK(!gpu_factories ||
-         (gpu_factories->GetTaskRunner() == media_task_runner.get()));
-
   // Prefer an external decoder since one will only exist if it is hardware
   // accelerated.
   if (gpu_factories) {
+    // |gpu_factories_| requires that its entry points be called on its
+    // |GetTaskRunner()|.  Since |pipeline_| will own decoders created from the
+    // factories, require that their message loops are identical.
+    DCHECK(gpu_factories->GetTaskRunner() == media_task_runner.get());
+
     if (decoder_factory_) {
       decoder_factory_->CreateVideoDecoders(media_task_runner, gpu_factories,
                                             &video_decoders);
     }
     video_decoders.push_back(
         new GpuVideoDecoder(gpu_factories, request_surface_cb));
   }
 
 #if !defined(MEDIA_DISABLE_LIBVPX)
   video_decoders.push_back(new VpxVideoDecoder());
@@ skipping 26 matching lines @@
   std::unique_ptr<VideoRenderer> video_renderer(new VideoRendererImpl(
       media_task_runner, worker_task_runner, video_renderer_sink,
       CreateVideoDecoders(media_task_runner, request_surface_cb, gpu_factories),
       true, gpu_factories, media_log_));
 
   return base::WrapUnique(new RendererImpl(
       media_task_runner, std::move(audio_renderer), std::move(video_renderer)));
 }
 
 }  // namespace media