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

ui/base/dragdrop/os_exchange_data.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 UI_BASE_DRAGDROP_OS_EXCHANGE_DATA_H_
 #define UI_BASE_DRAGDROP_OS_EXCHANGE_DATA_H_
 
 #include <memory>
 #include <set>
 #include <string>
@@ skipping 120 matching lines @@
 #endif
 
 #if defined(USE_AURA) || defined(OS_MACOSX)
     virtual void SetDragImage(const gfx::ImageSkia& image,
                               const gfx::Vector2d& cursor_offset) = 0;
     virtual const gfx::ImageSkia& GetDragImage() const = 0;
     virtual const gfx::Vector2d& GetDragImageOffset() const = 0;
 #endif
   };
 
-  // Creates the platform specific Provider.
-  static Provider* CreateProvider();
-
   OSExchangeData();
   // Creates an OSExchangeData with the specified provider. OSExchangeData
   // takes ownership of the supplied provider.
   explicit OSExchangeData(Provider* provider);
 
   ~OSExchangeData();
 
   // Returns the Provider, which actually stores and manages the data.
   const Provider& provider() const { return *provider_; }
   Provider& provider() { return *provider_; }
@@ skipping 76 matching lines @@
  private:
   // Provides the actual data.
   std::unique_ptr<Provider> provider_;
 
   DISALLOW_COPY_AND_ASSIGN(OSExchangeData);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_DRAGDROP_OS_EXCHANGE_DATA_H_