Remove threading from WifiDataProviderCommon.

content/browser/geolocation/empty_device_data_provider.h

 // 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.
 
 #ifndef CONTENT_BROWSER_GEOLOCATION_EMPTY_DEVICE_DATA_PROVIDER_H_
 #define CONTENT_BROWSER_GEOLOCATION_EMPTY_DEVICE_DATA_PROVIDER_H_
 
 #include "content/browser/geolocation/device_data_provider.h"
 
 namespace content {
 
 // An implementation of DeviceDataProviderImplBase that does not provide any
 // data. Used on platforms where a given data type is not available.
 
 template<typename DataType>
 class EmptyDeviceDataProvider : public DeviceDataProviderImplBase<DataType> {
  public:
   EmptyDeviceDataProvider() {}
   virtual ~EmptyDeviceDataProvider() {}
 
   // DeviceDataProviderImplBase implementation
-  virtual bool StartDataProvider() { return true; }
+  virtual void StartDataProvider() { }
   virtual void StopDataProvider() { }
   virtual bool GetData(DataType *data) {
     DCHECK(data);
     // This is all the data we can get - nothing.
     return true;
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(EmptyDeviceDataProvider);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_GEOLOCATION_EMPTY_DEVICE_DATA_PROVIDER_H_