Get drag and drop working for win aura.

ui/ui.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'includes': [
     'ui_resources.gypi',
@@ skipping 574 matching lines @@
           ],
         }],
         ['use_aura==1', {
           'sources/': [
             ['exclude', 'gfx/gtk_'],
             ['exclude', 'gfx/gtk_util.cc'],
             ['exclude', 'gfx/gtk_util.h'],
             ['exclude', 'gfx/screen_gtk.cc'],
             ['exclude', 'base/dialogs/select_file_dialog_mac.mm'],
             ['exclude', 'base/dialogs/select_file_dialog_win.cc'],
-            ['exclude', 'base/dragdrop/drag_utils_win.cc'],
             ['exclude', 'base/work_area_watcher_observer.h'],
             ['exclude', 'base/x/active_window_watcher_x.cc'],
             ['exclude', 'base/x/active_window_watcher_x.h'],
             ['exclude', 'base/x/active_window_watcher_x_observer.h'],
             ['exclude', 'base/x/root_window_property_watcher_x.cc'],
             ['exclude', 'base/x/root_window_property_watcher_x.h'],
             ['exclude', 'base/x/work_area_watcher_x.cc'],
             ['exclude', 'base/x/work_area_watcher_x.h'],
             ['exclude', 'ui_controls_win.cc'],
            ],
         }, {  # use_aura!=1
           'sources!': [
             'base/cursor/cursor.cc',
             'base/cursor/cursor.h',
             'base/cursor/cursor_loader_x11.cc',
             'base/cursor/cursor_loader_x11.h',
             'base/cursor/cursor_win.cc',
             'base/cursor/cursor_x11.cc',
           ]
         }],
         ['use_aura==1 and OS=="win"', {
           'sources/': [
-            ['exclude', 'base/dragdrop/os_exchange_data_provider_win.cc'],
-            ['exclude', 'base/dragdrop/os_exchange_data_provider_win.h'],
+            ['exclude', 'base/dragdrop/os_exchange_data_provider_aura.cc'],
+            ['exclude', 'base/dragdrop/drag_utils_aura.cc'],
           ],
         }],
         ['use_aura==0 and toolkit_views==0', {
           'sources/': [
             ['exclude', '^base/gestures/*'],
           ]
         }],
         ['use_aura==1 and use_ash==0 and OS=="linux"', {
           'sources': [
             'base/linux_ui.cc',
@@ skipping 257 matching lines @@
            },
            'dependencies': [
              '../base/base.gyp:base_java',
            ],
            'includes': [ '../build/java.gypi' ],
          },
        ],
     }],
   ],
 }