Encrypted Media: DecryptingXxx::SetDecryptor() accepts NULL decryptor.

media/filters/decrypting_demuxer_stream.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/decrypting_demuxer_stream.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/logging.h"
@@ skipping 118 matching lines @@
 DecryptingDemuxerStream::~DecryptingDemuxerStream() {}
 
 void DecryptingDemuxerStream::SetDecryptor(Decryptor* decryptor) {
   DVLOG(2) << "SetDecryptor()";
   DCHECK(message_loop_->BelongsToCurrentThread());
   DCHECK_EQ(state_, kDecryptorRequested) << state_;
   DCHECK(!init_cb_.is_null());
   DCHECK(!set_decryptor_ready_cb_.is_null());
 
   set_decryptor_ready_cb_.Reset();
+
+  if (!decryptor) {
+    base::ResetAndReturn(&init_cb_).Run(DECODER_ERROR_NOT_SUPPORTED);
+    state_ = kUninitialized;
+    return;
+  }
+
   decryptor_ = decryptor;
 
   decryptor_->RegisterNewKeyCB(
       GetDecryptorStreamType(),
       BIND_TO_LOOP(&DecryptingDemuxerStream::OnKeyAdded));
 
   state_ = kIdle;
   base::ResetAndReturn(&init_cb_).Run(PIPELINE_OK);
 }
 
@@ skipping 166 matching lines @@
       break;
     }
 
     default:
       NOTREACHED();
       return;
   }
 }
 
 }  // namespace media