Start plumbing drm atomic swap.

ui/ozone/platform/dri/dri.gypi

 # Copyright 2014 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': {
     'internal_ozone_platform_deps': [
       'ozone_platform_dri',
     ],
     'internal_ozone_platform_unittest_deps': [
       'ozone_platform_dri_unittests',
     ],
     'internal_ozone_platforms': [
       'dri',
     ],
+    'use_drm_atomic_flip%': 0,
   },
   'targets': [
     {
       'target_name': 'ozone_platform_dri',
       'type': 'static_library',
       'dependencies': [
         '../../base/base.gyp:base',
         '../../build/linux/system.gyp:dridrm',
         '../../skia/skia.gyp:skia',
         '../base/ui_base.gyp:ui_base',
@@ skipping 35 matching lines @@
         'ozone_platform_dri.cc',
         'ozone_platform_dri.h',
         'scoped_drm_types.cc',
         'scoped_drm_types.h',
         'screen_manager.cc',
         'screen_manager.h',
         'scanout_surface.h',
         'virtual_terminal_manager.cc',
         'virtual_terminal_manager.h',
       ],
+      'conditions': [
+        ['use_drm_atomic_flip==1', {
+          'sources': [
+            'hardware_display_plane.cc',
+            'hardware_display_plane.h',
+          ],
+        }],
+      ],      
     },
     {
       'target_name': 'ozone_platform_dri_unittests',
       'type': 'none',
       'dependencies': [
         '../../build/linux/system.gyp:dridrm',
         '../../skia/skia.gyp:skia',
         '../gfx/gfx.gyp:gfx_geometry',
         'ozone_platform_dri',
       ],
@@ skipping 12 matching lines @@
           'test/mock_dri_surface.h',
           'test/mock_dri_wrapper.cc',
           'test/mock_dri_wrapper.h',
           'test/mock_surface_generator.cc',
           'test/mock_surface_generator.h',
         ],
       },
     },
   ],
 }