Allow OSExchangeData::Provider to be overridden at run time.

ui/base/dragdrop/os_exchange_data_provider_win.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 "ui/base/dragdrop/os_exchange_data_provider_win.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 
@@ skipping 1047 matching lines @@
   wcsncpy_s(descriptor->fgd[0].cFileName, MAX_PATH, file_name.c_str(),
             std::min(file_name.size(), static_cast<size_t>(MAX_PATH - 1u)));
 
   STGMEDIUM* storage = new STGMEDIUM;
   storage->tymed = TYMED_HGLOBAL;
   storage->hGlobal = hdata;
   storage->pUnkForRelease = NULL;
   return storage;
 }
 
-///////////////////////////////////////////////////////////////////////////////
-// OSExchangeData, public:
-
-// static
-OSExchangeData::Provider* OSExchangeData::CreateProvider() {
-  return new OSExchangeDataProviderWin();
-}
-
 }  // namespace ui