[Mac] Remove no-op method in bookmark bar controller

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm

Index: chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
index cae85ebc58a7ebe57abb61222d337dfeaa843142..90b8de69e69efc3e0a231ffb1ec9acce327a36b1 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
@@ -2308,12 +2308,6 @@ static BOOL ValueInRangeInclusive(CGFloat low, CGFloat value, CGFloat high) {
   [self reconfigureBookmarkBar];
 }
 
-- (void)beingDeleted:(BookmarkModel*)model {
-  // The browser may be being torn down; little is safe to do.  As an
-  // example, it may not be safe to clear the pasteboard.
-  // http://crbug.com/38665
-}
-
 - (void)nodeAdded:(BookmarkModel*)model
            parent:(const BookmarkNode*)newParent index:(int)newIndex {
   // If a context menu is open, close it.