Encrypted Media: Refactor Video Decrypt-Only to use DecryptingDemuxerStream.

- Add VideoDecoderSelector to facilitate VideoDecoder initialization/selection.
- Add VideoDecoderSelectorTest.
- Remove DecryptingVideoDecoder from default decoder list.
- Disable decryption in FFmpegVideoDecoder.
- Updated all unittests.

After this CL, FFmpegVideoDecoder and ProxyDecryptor need to be cleaned.

BUG=141786
TEST=all tests pass; EME demos work.

Review URL: https://codereview.chromium.org/11573047

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@173562 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 10 insertions, 26 deletions

diff --git a/webkit/media/filter_helpers.cc b/webkit/media/filter_helpers.cc
index 1c1206c..362810c 100644
--- a/webkit/media/filter_helpers.cc
+++ b/webkit/media/filter_helpers.cc
@@ -7,7 +7,6 @@
 #include "base/bind.h"
 #include "media/base/filter_collection.h"
 #include "media/filters/chunk_demuxer.h"
-#include "media/filters/decrypting_video_decoder.h"
 #include "media/filters/dummy_demuxer.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
 #include "media/filters/ffmpeg_demuxer.h"
@@ -23,8 +22,7 @@ namespace webkit_media {
 // audio/video decoder in the |filter_collection| that supports the input
 // audio/video stream will be selected as the audio/video decoder in the media
 // pipeline. This is done by trying to initialize the decoder with the input
-// stream. Some decoder may only accept certain types of streams. For example,
-// DecryptingVideoDecoder only supports encrypted video stream.
+// stream. Some decoder may only accept certain types of streams.
 static void AddDefaultDecodersToCollection(
     const scoped_refptr<base::MessageLoopProxy>& message_loop,
     media::FilterCollection* filter_collection,
@@ -33,21 +31,6 @@ static void AddDefaultDecodersToCollection(
       new media::FFmpegAudioDecoder(message_loop);
   filter_collection->GetAudioDecoders()->push_back(ffmpeg_audio_decoder);
 
-  if (proxy_decryptor) {
-    scoped_refptr<media::DecryptingVideoDecoder> decrypting_video_decoder =
-        new media::DecryptingVideoDecoder(
-            message_loop,
-            base::Bind(&ProxyDecryptor::SetDecryptorReadyCB,
-                       base::Unretained(proxy_decryptor)));
-    // TODO(xhwang): Ideally we should have decrypting video decoder after
-    // regular video decoder since in the real world most videos are not
-    // encrypted. For now FFmpegVideoDecoder can also do decryption
-    // (decrypt-only), and we perfer DecryptingVideoDecoder (decrypt-and-decode)
-    // to FFmpegVideoDecoder. Fix this order when we move decryption out of
-    // FFmpegVideoDecoder.
-    filter_collection->GetVideoDecoders()->push_back(decrypting_video_decoder);
-  }
-
   scoped_refptr<media::FFmpegVideoDecoder> ffmpeg_video_decoder =
       new media::FFmpegVideoDecoder(message_loop, proxy_decryptor);
   filter_collection->GetVideoDecoders()->push_back(ffmpeg_video_decoder);
diff --git a/webkit/media/webmediaplayer_impl.cc b/webkit/media/webmediaplayer_impl.cc
index 37f0889..f9cb47c 100644
--- a/webkit/media/webmediaplayer_impl.cc
+++ b/webkit/media/webmediaplayer_impl.cc
@@ -178,24 +178,25 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
   // Also we want to be notified of |main_loop_| destruction.
   main_loop_->AddDestructionObserver(this);
 
+  media::SetDecryptorReadyCB set_decryptor_ready_cb;
+  if (WebKit::WebRuntimeFeatures::isEncryptedMediaEnabled()) {
+    decryptor_.reset(new ProxyDecryptor(message_loop_factory_->GetMessageLoop(
+        media::MessageLoopFactory::kPipeline), proxy_.get(), client, frame));
+    set_decryptor_ready_cb = base::Bind(&ProxyDecryptor::SetDecryptorReadyCB,
+                                        base::Unretained(decryptor_.get()));
+  }
+
   // Create default video renderer.
   scoped_refptr<media::VideoRendererBase> video_renderer =
       new media::VideoRendererBase(
           pipeline_message_loop,
+          set_decryptor_ready_cb,
           base::Bind(&WebMediaPlayerProxy::Repaint, proxy_),
           BIND_TO_RENDER_LOOP(&WebMediaPlayerImpl::SetOpaque),
           true);
   filter_collection_->AddVideoRenderer(video_renderer);
   proxy_->set_frame_provider(video_renderer);
 
-  media::SetDecryptorReadyCB set_decryptor_ready_cb;
-  if (WebKit::WebRuntimeFeatures::isEncryptedMediaEnabled()) {
-    decryptor_.reset(new ProxyDecryptor(message_loop_factory_->GetMessageLoop(
-        media::MessageLoopFactory::kPipeline), proxy_.get(), client, frame));
-    set_decryptor_ready_cb = base::Bind(&ProxyDecryptor::SetDecryptorReadyCB,
-                                        base::Unretained(decryptor_.get()));
-  }
-
   // Create default audio renderer using the null sink if no sink was provided.
   if (!audio_renderer_sink)
     audio_renderer_sink = new media::NullAudioSink();