Remove the ENABLE_GPU #define and enable_gpu gyp variable

content/content_common.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base',
     '../components/tracing.gyp:tracing',
     '../net/net.gyp:net',
     '../skia/skia.gyp:skia',
@@ skipping 386 matching lines @@
         ['include', '^common/media/media_stream_options\\.cc$'],
         ['include', '^common/net/url_fetcher\\.cc$'],
         ['include', '^common/net/url_request_user_data\\.cc$'],
         ['include', '^common/page_state_serialization\\.cc$'],
         ['include', '^common/savable_url_schemes\\.cc$'],
         ['include', '^common/url_schemes\\.cc$'],
       ],
     }, {  # OS!="ios"
       'dependencies': [
         '../cc/cc.gyp:cc',
+        '../gpu/gpu.gyp:command_buffer_service',
         '../gpu/gpu.gyp:gles2_c_lib',
         '../gpu/gpu.gyp:gles2_implementation',
         '../gpu/gpu.gyp:gpu_ipc',
         '../ipc/ipc.gyp:ipc',
         '../media/media.gyp:media',
         '../media/media.gyp:shared_memory_support',
         '../ui/gl/gl.gyp:gl',
         '../webkit/common/webkit_common.gyp:webkit_common',
         '../webkit/storage_browser.gyp:webkit_storage_browser',
         '../webkit/storage_common.gyp:webkit_storage_common',
@@ skipping 60 matching lines @@
         '../ppapi/ppapi_internal.gyp:ppapi_shared',
       ],
     }, {  # enable_plugins == 0
       'sources!': [
         'common/font_list.cc',
         'common/pepper_plugin_list.cc',
         'common/pepper_plugin_list.h',
         'common/sandbox_util.cc',
       ],
     }],
-    ['enable_gpu==1', {
-      'dependencies': [
-        '../gpu/gpu.gyp:command_buffer_service',
-      ],
-    }],
     ['OS=="android"', {
       'dependencies': [
         '../media/media.gyp:media',
       ],
       'sources': [
         'common/gpu/media/android_video_decode_accelerator.cc',
         'common/gpu/media/android_video_decode_accelerator.h',
       ],
     }],
     ['target_arch=="arm" and chromeos == 1 and use_x11 == 1', {
@@ skipping 85 matching lines @@
         '..\\third_party\\directxsdk\\files\\Redist\\<(input)',
         '<(output)',
         '<(PRODUCT_DIR)',
         ],
         'msvs_cygwin_shell': 1,
       },
      ]
     }],
   ],
 }