events: Create a separate platforms target.

components/bookmarks.gypi

 # Copyright 2014 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.
 
 {
   'targets': [
     {
       'target_name': 'bookmarks_core_browser',
       'type': 'static_library',
       'include_dirs': [
@@ skipping 64 matching lines @@
       ],
     },
     {
       'target_name': 'bookmarks_core_test_support',
       'type': 'static_library',
       'include_dirs': [
         '..',
       ],
       'dependencies': [
         '../base/base.gyp:base',
+        '../ui/events/platform/events_platform.gyp:events_platform',
         '../url/url.gyp:url_lib',
         'bookmarks_core_browser',
       ],
       'sources': [
         'bookmarks/core/test/bookmark_test_helpers.cc',
         'bookmarks/core/test/bookmark_test_helpers.h',
         'bookmarks/core/test/test_bookmark_client.cc',
         'bookmarks/core/test/test_bookmark_client.h',
       ],
+      'conditions': [
+        ['use_x11==1', {
+          'dependencies': [
+            '../ui/events/platform/x11/x11_events_platform.gyp:x11_events_platform',
+          ],
+        }],
+      ],
     },
   ],
 }