Delete MacVDA from the codebase since it is dead code and not being worked on.

chrome/browser/about_flags.cc

 // 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.
 
 #include "chrome/browser/about_flags.h"
 
 #include <string.h>
 
 #include <algorithm>
 #include <iterator>
@@ skipping 1082 matching lines @@
   {
     "enable-new-dialog-style",
     IDS_FLAGS_ENABLE_NEW_DIALOG_STYLE_NAME,
     IDS_FLAGS_ENABLE_NEW_DIALOG_STYLE_DESCRIPTION,
     kOsWin | kOsCrOS,
     SINGLE_VALUE_TYPE(switches::kEnableNewDialogStyle),
   },
   { "disable-accelerated-video-decode",
     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_NAME,
     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_DESCRIPTION,
-    kOsDesktop,
+    kOsWin | kOsCrOS,
     SINGLE_VALUE_TYPE(switches::kDisableAcceleratedVideoDecode),
   },
 #if defined(USE_ASH)
   {
     "ash-debug-shortcuts",
     IDS_FLAGS_DEBUG_SHORTCUTS_NAME,
     IDS_FLAGS_DEBUG_SHORTCUTS_DESCRIPTION,
     kOsAll,
     SINGLE_VALUE_TYPE(ash::switches::kAshDebugShortcuts),
   },
@@ skipping 786 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags