Makes test_web_graphics_context_3d only compile if

ui/gfx/compositor/compositor.gyp

 # 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': {
     'chromium_code': 1,
   },
   'target_defaults': {
     'sources/': [
@@ skipping 89 matching lines @@
             'dependencies': [
               '<(DEPTH)/third_party/WebKit/Source/WebKit/chromium/WebKit.gyp:webkit',
               '<(DEPTH)/webkit/support/webkit_support.gyp:fileapi',
               '<(DEPTH)/webkit/support/webkit_support.gyp:glue',
               '<(DEPTH)/webkit/support/webkit_support.gyp:webkit_gpu',
             ],
           }, {
             'sources!': [
               'compositor_cc.cc',
               'compositor_cc.h',
+              'test_web_graphics_context_3d.cc',
+              'test_web_graphics_context_3d.h',
             ],
           }
         ],
       ],
     },
     {
       'target_name': 'compositor_test_support',
       'type': 'static_library',
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base',
@@ skipping 89 matching lines @@
             'test/test_compositor.cc',
             'test/test_compositor.h',
             'test/test_texture.cc',
             'test/test_texture.h',
           ],
         }],
       ],
     },
   ],
 }