Restructure the events target into two components:

content/content_tests.gypi

 # Copyright (c) 2013 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': 'test_support_content',
       'type': 'static_library',
       'dependencies': [
         '../net/net.gyp:net_test_support',
         '../skia/skia.gyp:skia',
         '../testing/gmock.gyp:gmock',
         '../testing/gtest.gyp:gtest',
-        '../ui/events/events.gyp:events',
+        '../ui/events/events.gyp:events_base',
         '../ui/gfx/gfx.gyp:gfx',
         '../ui/ui.gyp:keycode_converter',
         '../ui/ui.gyp:ui',
         '../ui/ui.gyp:ui_resources',
         '../ui/ui_unittests.gyp:ui_test_support',
         '../url/url.gyp:url_lib',
         'browser/speech/proto/speech_proto.gyp:speech_proto',
         'content.gyp:content_app_both',
         'content.gyp:content_browser',
         'content.gyp:content_common',
@@ skipping 1571 matching lines @@
                   'files': ['<(PRODUCT_DIR)/libnpapi_test_plugin.so'],
                 },
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }