Add ANGLE Platform implementation.

ui/gl/gl.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': {
     'chromium_code': 1,
   },
 
   'targets': [
@@ skipping 168 matching lines @@
           'dependencies': [
             '<(DEPTH)/build/linux/system.gyp:x11',
             '<(DEPTH)/build/linux/system.gyp:xcomposite',
             '<(DEPTH)/build/linux/system.gyp:xext',
             '<(DEPTH)/ui/events/platform/events_platform.gyp:events_platform',
             '<(DEPTH)/ui/gfx/x/gfx_x11.gyp:gfx_x11',
           ],
         }],
         ['OS=="win"', {
           'sources': [
+            'angle_platform_impl.cc',
+            'angle_platform_impl.h',
             'gl_bindings_autogen_wgl.cc',
             'gl_bindings_autogen_wgl.h',
             'gl_context_wgl.cc',
             'gl_context_wgl.h',
             'gl_egl_api_implementation.cc',
             'gl_egl_api_implementation.h',
             'gl_surface_wgl.cc',
             'gl_surface_wgl.h',
             'gl_wgl_api_implementation.cc',
             'gl_wgl_api_implementation.h',
@@ skipping 113 matching lines @@
           ],
           'variables': {
             'jni_gen_package': 'ui/gl',
           },
           'includes': [ '../../build/jni_generator.gypi' ],
         },
       ],
     }],
   ],
 }