Expose the MacViewsWebUIDialogs feature flag to chrome://flags

chrome/common/chrome_switches.h

 // 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.
 
 // Defines the shared command-line switches used by code in the Chrome
 // directory that don't have anywhere more specific to go.
 
 #ifndef CHROME_COMMON_CHROME_SWITCHES_H_
 #define CHROME_COMMON_CHROME_SWITCHES_H_
 
@@ skipping 328 matching lines @@
 extern const char kDisableHostedAppShimCreation[];
 extern const char kDisableHostedAppsInWindows[];
 extern const char kDisableMacViewsNativeAppWindows[];
 extern const char kDisableTranslateNewUX[];
 extern const char kEnableAppInfoDialogMac[];
 extern const char kEnableAppWindowCycling[];
 extern const char kEnableFullscreenLowPowerMode[];
 extern const char kEnableFullscreenTabDetaching[];
 extern const char kEnableHostedAppsInWindows[];
 extern const char kEnableMacViewsNativeAppWindows[];
-extern const char kEnableMacViewsDialogs[];
 extern const char kEnableTranslateNewUX[];
 extern const char kMetricsClientID[];
 extern const char kRelauncherProcess[];
 extern const char kRelauncherProcessDMGDevice[];
 #endif  // defined(OS_MACOSX)
 
 #if defined(OS_WIN)
 extern const char kEnableCloudPrintXps[];
 extern const char kEnableProfileShortcutManager[];
 extern const char kHideIcons[];
@@ skipping 40 matching lines @@
 #if defined(OS_CHROMEOS)
 bool PowerOverlayEnabled();
 #endif
 
 // DON'T ADD RANDOM STUFF HERE. Put it in the main section above in
 // alphabetical order, or in one of the ifdefs (also in order in each section).
 
 }  // namespace switches
 
 #endif  // CHROME_COMMON_CHROME_SWITCHES_H_