Make it possible to test command buffer decoder functions with extension flags

gpu/gpu.gyp

 # 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.
 
 {
   'variables': {
     'nacl_win64_target': 0,
   },
   'includes': [
     'gpu_common.gypi',
@@ skipping 228 matching lines @@
         'command_buffer/service/gles2_cmd_decoder_unittest_1_autogen.h',
         'command_buffer/service/gles2_cmd_decoder_unittest_2.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_2_autogen.h',
         'command_buffer/service/gles2_cmd_decoder_unittest_3.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_3_autogen.h',
         'command_buffer/service/gles2_cmd_decoder_unittest_async_pixel.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_base.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_base.h',
         'command_buffer/service/gles2_cmd_decoder_unittest_context_state.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_drawing.cc',
+        'command_buffer/service/gles2_cmd_decoder_unittest_extensions.cc',
+        'command_buffer/service/gles2_cmd_decoder_unittest_extensions_autogen.h',
         'command_buffer/service/gles2_cmd_decoder_unittest_framebuffers.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_programs.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_textures.cc',
         'command_buffer/service/gles2_cmd_decoder_unittest_attribs.cc',
         'command_buffer/service/gl_surface_mock.cc',
         'command_buffer/service/gl_surface_mock.h',
         'command_buffer/service/gpu_scheduler_unittest.cc',
         'command_buffer/service/gpu_service_test.cc',
         'command_buffer/service/gpu_service_test.h',
         'command_buffer/service/id_manager_unittest.cc',
@@ skipping 401 matching lines @@
           ],
           'variables': {
             'test_suite_name': 'gpu_unittests',
           },
           'includes': [ '../build/apk_test.gypi' ],
         },
       ],
     }],
   ],
 }