Add support for encrypted WebM files as defined in the RFC.

media/filters/pipeline_integration_test_base.cc

Index: media/filters/pipeline_integration_test_base.cc
diff --git a/media/filters/pipeline_integration_test_base.cc b/media/filters/pipeline_integration_test_base.cc
index e6a58f5ba25c795f18f4d3e1b25c105f8b8a35c7..4e2a89856eb1ecac4188c0ec1224b104fe91d0fc 100644
--- a/media/filters/pipeline_integration_test_base.cc
+++ b/media/filters/pipeline_integration_test_base.cc
@@ -6,7 +6,7 @@
 
 #include "base/bind.h"
 #include "media/base/media_log.h"
-#include "media/crypto/aes_decryptor.h"
+#include "media/crypto/hmac_aes_decryptor.h"
 #include "media/filters/audio_renderer_impl.h"
 #include "media/filters/chunk_demuxer.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
@@ -188,7 +188,7 @@ PipelineIntegrationTestBase::CreateFilterCollection(
     const scoped_refptr<Demuxer>& demuxer) {
   scoped_ptr<FilterCollection> collection(new FilterCollection());
   collection->SetDemuxer(demuxer);
-  decryptor_.reset(new AesDecryptor());
+  decryptor_.reset(new HmacAesDecryptor());
   collection->AddAudioDecoder(new FFmpegAudioDecoder(
       base::Bind(&MessageLoopFactory::GetMessageLoop,
                  base::Unretained(message_loop_factory_.get()),