dbus: Fix a bug where we were emitting spurious error messages.

dbus/object_proxy.h

 // 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.
 
 #ifndef DBUS_OBJECT_PROXY_H_
 #define DBUS_OBJECT_PROXY_H_
 #pragma once
 
 #include <dbus/dbus.h>
 
 #include <map>
+#include <set>
 #include <string>
-#include <vector>
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/time.h"
 
 namespace dbus {
 
 class Bus;
 class MethodCall;
 class Response;
@@ skipping 161 matching lines @@
   std::string object_path_;
 
   // True if the message filter was added.
   bool filter_added_;
 
   // The method table where keys are absolute signal names (i.e. interface
   // name + signal name), and values are the corresponding callbacks.
   typedef std::map<std::string, SignalCallback> MethodTable;
   MethodTable method_table_;
 
-  std::vector<std::string> match_rules_;
+  std::set<std::string> match_rules_;
 
   DISALLOW_COPY_AND_ASSIGN(ObjectProxy);
 };
 
 }  // namespace dbus
 
 #endif  // DBUS_OBJECT_PROXY_H_