Attempt 3 at:

chrome/chrome_tests.gypi

 # Copyright (c) 2011 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' : {
     'pyautolib_sources': [
       'app/chrome_command_ids.h',
       'app/chrome_dll_resource.h',
       'common/automation_constants.h',
       'common/pref_names.cc',
@@ skipping 47 matching lines @@
         '../content/content.gyp:test_support_content',
         '../ipc/ipc.gyp:test_support_ipc',
         '../media/media.gyp:media_test_support',
         '../net/net.gyp:net',
         # 'test/base/test_url_request_context_getter.h' brings in this requirement.
         '../net/net.gyp:net_test_support',
         '../skia/skia.gyp:skia',
         '../testing/gmock.gyp:gmock',
         '../testing/gtest.gyp:gtest',
         '../third_party/leveldatabase/leveldatabase.gyp:leveldatabase',
-        '../ui/gfx/compositor/compositor.gyp:test_compositor',
         '../ui/gfx/compositor/compositor.gyp:compositor_test_support',
       ],
       'export_dependent_settings': [
         'renderer',
         'app/policy/cloud_policy_codegen.gyp:policy',
         '../base/base.gyp:test_support_base',
       ],
       'include_dirs': [
         '..',
       ],
@@ skipping 193 matching lines @@
         ['OS=="win"', {
           'include_dirs': [
             '<(DEPTH)/third_party/wtl/include',
           ],
         }],
         ['OS=="win" and use_aura==1', {
           'sources/': [
             ['exclude', 'test/base/ui_test_utils_win.cc'],
           ],
         }],
+        ['use_webkit_compositor==0', {
+          'dependencies': [
+            '../ui/gfx/compositor/compositor.gyp:test_compositor',
+          ],
+        }],
       ],
     },
     {
       'target_name': 'test_support_ui',
       'type': 'static_library',
       'dependencies': [
         'chrome_resources.gyp:chrome_resources',
         'chrome_resources.gyp:chrome_strings',
         'chrome_resources.gyp:theme_resources',
         'test_support_common',
@@ skipping 4023 matching lines @@
               # Use outputs of this action as inputs for the main target build.
               # Seems as a misnomer but makes this happy on Linux (scons).
               'process_outputs_as_sources': 1,
             },
           ],  # 'actions'
         },
       ]
     }],  # 'coverage!=0'
   ],  # 'conditions'
 }