Sprinkle some CHECK()s in media::VideoRendererBase to help track down a crash.

media/filters/video_renderer_base.cc

 // Copyright (c) 2012 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/filters/video_renderer_base.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/message_loop.h"
@@ skipping 435 matching lines @@
     return;
   }
 
   if (state_ == kError || state_ == kStopped) {
     DoStopOrError_Locked();
   }
 }
 
 VideoRendererBase::~VideoRendererBase() {
   base::AutoLock auto_lock(lock_);
-  DCHECK(state_ == kUninitialized || state_ == kStopped) << state_;
+  CHECK(state_ == kUninitialized || state_ == kStopped) << state_;
+  CHECK_EQ(thread_, base::kNullThreadHandle);
 }
 
 void VideoRendererBase::FrameReady(VideoDecoder::Status status,
                                    const scoped_refptr<VideoFrame>& frame) {
   base::AutoLock auto_lock(lock_);
   DCHECK_NE(state_, kUninitialized);
 
   CHECK(pending_read_);
   pending_read_ = false;
 
@@ skipping 200 matching lines @@
 
 int VideoRendererBase::NumFrames_Locked() const {
   lock_.AssertAcquired();
   int outstanding_frames =
       (current_frame_ ? 1 : 0) + (last_available_frame_ ? 1 : 0) +
       (current_frame_ && (current_frame_ == last_available_frame_) ? -1 : 0);
   return ready_frames_.size() + outstanding_frames;
 }
 
 }  // namespace media