ozone: Add atomic initialization path

ui/ozone/public/ozone_switches.cc

 // 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.
 
 #include "ui/ozone/public/ozone_switches.h"
 
 namespace switches {
 
 // Specify ozone platform implementation to use.
 const char kOzonePlatform[] = "ozone-platform";
 
 // Specify location for image dumps.
 const char kOzoneDumpFile[] = "ozone-dump-file";
 
 // Specify if the accelerated path should use surfaceless rendering. In this
 // mode there is no EGL surface.
 const char kOzoneUseSurfaceless[] = "ozone-use-surfaceless";
 
 // Enable support for a single overlay plane.
 const char kOzoneTestSingleOverlaySupport[] =
     "ozone-test-single-overlay-support";
 
 // Specifies the size of the primary display at initialization.
 const char kOzoneInitialDisplayBounds[] = "ozone-initial-display-bounds";
 
 // Specifies the physical display size in millimeters.
 const char kOzoneInitialDisplayPhysicalSizeMm[] =
     "ozone-initial-display-physical-size-mm";
 
+// Enables atomic API support, if supported by the driver.
+const char kOzoneUseAtomicDrm[] = "ozone-use-atomic-drm";
+
 }  // namespace switches