refactor EnumerateDevices to make it a persistent request.

webkit/plugins/ppapi/ppb_audio_input_impl.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 "webkit/plugins/ppapi/ppb_audio_input_impl.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/shared_memory.h"
@@ skipping 157 matching lines @@
 }
 
 void PPB_AudioInput_Impl::EnumerateDevicesCallbackFunc(
     int request_id,
     bool succeeded,
     const DeviceRefDataVector& devices) {
   devices_data_.clear();
   if (succeeded)
     devices_data_ = devices;
 
+  PluginDelegate* plugin_delegate = ResourceHelper::GetPluginDelegate(this);
+  if (plugin_delegate)
+    plugin_delegate->StopEnumerateDevices(request_id);
+
   OnEnumerateDevicesComplete(succeeded ? PP_OK : PP_ERROR_FAILED, devices);
 }
 
 }  // namespace ppapi
 }  // namespace webkit