[Mac] Reverse bookmark buttons and menus in RTL (take 2)

chrome/browser/ui/cocoa/l10n_util.h

 // Copyright (c) 2010 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.
 
 #ifndef CHROME_BROWSER_UI_COCOA_L10N_UTIL_H_
 #define CHROME_BROWSER_UI_COCOA_L10N_UTIL_H_
 
 #import <Cocoa/Cocoa.h>
 #include <stddef.h>
 
@@ skipping 34 matching lines @@
 // If ExperimentalMacRTL becomes the default, this function can be replaced with
 // uses of base::i18n::IsRTL().
 bool ShouldDoExperimentalRTLLayout();
 
 // Returns true if ShouldDoExperimentalRTLLayout() is true and the OS is
 // 10.12 or above. macOS 10.12 is the first OS where the native stoplight
 // buttons are reversed in RTL, so manually reversing them in previous
 // OSes would make Chrome stick out.
 bool ShouldFlipWindowControlsInRTL();
 
+// Returns NSImageLeading when available (10.12+), otherwise
+// NSImageLeft for LTR and NSImageRight in RTL.
+NSCellImagePosition LeadingCellImagePosition();
+// Returns NSImageTrailing when available (10.12+), otherwise
+// NSImageRight for LTR and NSImageLeft in RTL.
+NSCellImagePosition TrailingCellImagePosition();
+
 // Returns an autoreleased image containing |image| flipped
 // across the x axis.
 NSImage* FlippedImage(NSImage* image);
 
 }  // namespace cocoa_l10n_util
 
 #endif  // CHROME_BROWSER_UI_COCOA_L10N_UTIL_H_