Mac/clang: Possibly contentious changes.

chrome/browser/cocoa/extensions/browser_action_button.h

Index: chrome/browser/cocoa/extensions/browser_action_button.h
diff --git a/chrome/browser/cocoa/extensions/browser_action_button.h b/chrome/browser/cocoa/extensions/browser_action_button.h
index da701d88629fcaf1a3d5544a9d18b58a91f650b0..ffd8240efe41b7c9dcf445be8c7bab684cd11a65 100644
--- a/chrome/browser/cocoa/extensions/browser_action_button.h
+++ b/chrome/browser/cocoa/extensions/browser_action_button.h
@@ -18,12 +18,12 @@ class Profile;
 
 // Fired when the Browser Action's state has changed. Usually the image needs to
 // be updated.
-extern const NSString* kBrowserActionButtonUpdatedNotification;
+extern NSString* const kBrowserActionButtonUpdatedNotification;
 
 // Fired on each drag event while the user is moving the button.
-extern const NSString* kBrowserActionButtonDraggingNotification;
+extern NSString* const kBrowserActionButtonDraggingNotification;
 // Fired when the user drops the button.
-extern const NSString* kBrowserActionButtonDragEndNotification;
+extern NSString* const kBrowserActionButtonDragEndNotification;
 
 extern const CGFloat kBrowserActionWidth;