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

chrome/browser/speech/tts_message_filter.cc

 // Copyright (c) 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/speech/tts_message_filter.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/speech/tts_controller.h"
 #include "chrome/browser/speech/tts_message_filter.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/render_process_host.h"
 
 using content::BrowserThread;
 
 TtsMessageFilter::TtsMessageFilter(int render_process_id, Profile* profile)
-    : BrowserMessageFilter(TtsMsgStart),
-      render_process_id_(render_process_id),
+    : render_process_id_(render_process_id),
       profile_(profile) {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   TtsController::GetInstance()->AddVoicesChangedDelegate(this);
 }
 
 void TtsMessageFilter::OverrideThreadForMessage(
     const IPC::Message& message, BrowserThread::ID* thread) {
   switch (message.type()) {
   case TtsHostMsg_InitializeVoiceList::ID:
   case TtsHostMsg_Speak::ID:
@@ skipping 124 matching lines @@
   OnInitializeVoiceList();
 }
 
 void TtsMessageFilter::OnChannelClosingInUIThread() {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   TtsController::GetInstance()->RemoveVoicesChangedDelegate(this);
 }
 
 TtsMessageFilter::~TtsMessageFilter() {
 }