Reland: Implement Aura side of unified touch text selection for contents

ui/aura/aura.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,
   },
   'targets': [
     {
@@ skipping 38 matching lines @@
         'client/screen_position_client.h',
         'client/visibility_client.cc',
         'client/visibility_client.h',
         'client/window_stacking_client.cc',
         'client/window_stacking_client.h',
         'client/window_tree_client.cc',
         'client/window_tree_client.h',
         'env.cc',
         'env.h',
         'env_observer.h',
+        'image_window_delegate.cc',
+        'image_window_delegate.h',
         'input_state_lookup.cc',
         'input_state_lookup.h',
         'input_state_lookup_win.cc',
         'input_state_lookup_win.h',
         'layout_manager.cc',
         'layout_manager.h',
         'remote_window_tree_host_win.cc',
         'remote_window_tree_host_win.h',
         'scoped_window_targeter.cc',
         'scoped_window_targeter.h',
@@ skipping 235 matching lines @@
         ['OS=="linux" and use_allocator!="none"', {
           'dependencies': [
            # See http://crbug.com/162998#c4 for why this is needed.
             '../../base/allocator/allocator.gyp:allocator',
           ],
         }],
       ],
     },
   ],
 }