Mac. Ensure no more than one visibly selected item in each bookmark folder menu.

chrome/browser/ui/cocoa/gradient_button_cell.mm

 // Copyright (c) 2011 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/ui/cocoa/gradient_button_cell.h"
 
 #include "base/logging.h"
 #import "base/memory/scoped_nsobject.h"
 #import "chrome/browser/themes/theme_service.h"
 #import "chrome/browser/ui/cocoa/image_utils.h"
@@ skipping 705 matching lines @@
                      clipPath:&boundingPath];
   return boundingPath;
 }
 
 - (void)resetCursorRect:(NSRect)cellFrame inView:(NSView*)controlView {
   [super resetCursorRect:cellFrame inView:controlView];
   if (trackingArea_)
     [self updateTrackingAreas];
 }
 
-- (void)updateTrackingAreas {
+- (BOOL)isMouseReallyInside {
   BOOL mouseInView = NO;
   NSView* controlView = [self controlView];
   NSWindow* window = [controlView window];
   NSRect bounds = [controlView bounds];
   if (window) {
     NSPoint mousePoint = [window mouseLocationOutsideOfEventStream];
     mousePoint = [controlView convertPointFromBase:mousePoint];
     mouseInView = [controlView mouse:mousePoint inRect:bounds];
   }
+  return mouseInView;
+}
+
+- (void)updateTrackingAreas {
+  NSView* controlView = [self controlView];
+  BOOL mouseInView = [self isMouseReallyInside];
 
   if (trackingArea_.get())
     [controlView removeTrackingArea:trackingArea_];
 
   NSTrackingAreaOptions options = NSTrackingMouseEnteredAndExited |
                                   NSTrackingActiveInActiveApp;
   if (mouseInView)
     options |= NSTrackingAssumeInside;
 
   trackingArea_.reset([[NSTrackingArea alloc]
-                        initWithRect:bounds
+                        initWithRect:[controlView bounds]
                              options:options
                                owner:self
                             userInfo:nil]);
   if (isMouseInside_ != mouseInView) {
-    isMouseInside_ = mouseInView;
+    [self setMouseInside:mouseInView animate:NO];
     [controlView setNeedsDisplay:YES];
   }
 }
 
 @end