Revert "Allow MessageFilters to restrict listening to specific message classes"

chrome/browser/media/encrypted_media_message_filter_android.cc

 // Copyright 2013 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 "chrome/browser/media/encrypted_media_message_filter_android.h"
 
 #include <string>
 
 #include "chrome/common/encrypted_media_messages_android.h"
 #include "ipc/ipc_message_macros.h"
@@ skipping 27 matching lines @@
   if ((requested_codecs & android::MP4_AVC1) &&
       MediaCodecBridge::CanDecode("avc1", !video_must_be_compositable)) {
     supported_codecs = static_cast<android::SupportedCodecs>(
         supported_codecs | android::MP4_AVC1);
   }
 #endif  // defined(USE_PROPRIETARY_CODECS)
 
   return supported_codecs;
 }
 
-EncryptedMediaMessageFilterAndroid::EncryptedMediaMessageFilterAndroid()
-    : BrowserMessageFilter(EncryptedMediaMsgStart) {}
+EncryptedMediaMessageFilterAndroid::EncryptedMediaMessageFilterAndroid() {}
 
 EncryptedMediaMessageFilterAndroid::~EncryptedMediaMessageFilterAndroid() {}
 
 bool EncryptedMediaMessageFilterAndroid::OnMessageReceived(
     const IPC::Message& message, bool* message_was_ok) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP_EX(
       EncryptedMediaMessageFilterAndroid, message, *message_was_ok)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_GetSupportedKeySystems,
                         OnGetSupportedKeySystems)
@@ skipping 23 matching lines @@
   DCHECK_EQ(request.codecs >> 3, 0) << "unrecognized codec";
   response->uuid = request.uuid;
   // TODO(qinmin): check composition is supported or not.
   response->compositing_codecs =
       GetSupportedCodecs(request.codecs, true);
   response->non_compositing_codecs =
       GetSupportedCodecs(request.codecs, false);
 }
 
 }  // namespace chrome