Disable the gyp includes related to the OpenGL embedder, so that those who don't have freeglut can …

dart.gyp

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. 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': 'compiler',
       'type': 'none',
       'dependencies': [
@@ skipping 114 matching lines @@
         ],
         ['OS=="win"', {
            'dependencies': [
              'samples/sample_extension/sample_extension.gyp:sample_extension',
            ],
           },
         ],
         ['OS=="mac" or OS=="linux"', {
            'dependencies': [
              'samples/sample_extension/sample_extension.gyp:sample_extension',
-             'samples/mobile_emulator_sample/mobile_emulator_sample.gyp:mobile_emulator_sample',
            ],
           },
         ],
       ]
     },
     {
       'target_name': 'packages',
       'type': 'none',
       'dependencies': [
         'pkg/pkg.gyp:pkg_packages',
       ],
     },
   ],
 }