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

content/browser/devtools/worker_devtools_message_filter.cc

 // Copyright (c) 2011 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 "content/browser/devtools/worker_devtools_message_filter.h"
 
 #include "content/browser/devtools/worker_devtools_manager.h"
 #include "content/common/devtools_messages.h"
 #include "content/common/worker_messages.h"
 
 namespace content {
 
 WorkerDevToolsMessageFilter::WorkerDevToolsMessageFilter(
     int worker_process_host_id)
-    : BrowserMessageFilter(DevToolsMsgStart),
-      worker_process_host_id_(worker_process_host_id),
+    : worker_process_host_id_(worker_process_host_id),
       current_routing_id_(0) {
 }
 
 WorkerDevToolsMessageFilter::~WorkerDevToolsMessageFilter() {
 }
 
 bool WorkerDevToolsMessageFilter::OnMessageReceived(
     const IPC::Message& message,
     bool* message_was_ok) {
   bool handled = true;
@@ skipping 15 matching lines @@
       worker_process_host_id_, current_routing_id_, message);
 }
 
 void WorkerDevToolsMessageFilter::OnSaveAgentRumtimeState(
     const std::string& state) {
   WorkerDevToolsManager::GetInstance()->SaveAgentRuntimeState(
       worker_process_host_id_, current_routing_id_, state);
 }
 
 }  // namespace content