Fold {Audio|Video}Decoder::Stop() into the dtor.

media/filters/vpx_video_decoder.cc

Index: media/filters/vpx_video_decoder.cc
diff --git a/media/filters/vpx_video_decoder.cc b/media/filters/vpx_video_decoder.cc
index 20416f148077568de3b190e17dd571d1f80ca86f..9cadbca36c332418cde31bf269046d623d0c7054 100644
--- a/media/filters/vpx_video_decoder.cc
+++ b/media/filters/vpx_video_decoder.cc
@@ -209,7 +209,7 @@ VpxVideoDecoder::VpxVideoDecoder(
       vpx_codec_alpha_(NULL) {}
 
 VpxVideoDecoder::~VpxVideoDecoder() {
-  DCHECK_EQ(kUninitialized, state_);
+  DCHECK(task_runner_->BelongsToCurrentThread());
   CloseDecoder();
 }
 
@@ -338,12 +338,6 @@ void VpxVideoDecoder::Reset(const base::Closure& closure) {
   task_runner_->PostTask(FROM_HERE, closure);
 }
 
-void VpxVideoDecoder::Stop() {
-  DCHECK(task_runner_->BelongsToCurrentThread());
-
-  state_ = kUninitialized;
-}
-
 void VpxVideoDecoder::DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK_NE(state_, kUninitialized);