[Mac] Integrate divider into browser-action overflow chevron.

chrome/browser/cocoa/extensions/chevron_menu_button_cell.h

Index: chrome/browser/cocoa/extensions/chevron_menu_button_cell.h
diff --git a/chrome/browser/cocoa/extensions/chevron_menu_button_cell.h b/chrome/browser/cocoa/extensions/chevron_menu_button_cell.h
new file mode 100644
index 0000000000000000000000000000000000000000..c3217e3ed8fe868bc041b2d6fbb7521b9dab6d1f
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+++ b/chrome/browser/cocoa/extensions/chevron_menu_button_cell.h
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+// 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_COCOA_EXTENSIONS_CHEVRON_MENU_BUTTON_CELL_H_
+#define CHROME_BROWSER_COCOA_EXTENSIONS_CHEVRON_MENU_BUTTON_CELL_H_
+#pragma once
+
+#import "chrome/browser/cocoa/clickhold_button_cell.h"
+
+@interface ChevronMenuButtonCell : ClickHoldButtonCell {
+}
+
+// Adds a gradient border to the RHS of the cell when not hovered.
+- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView*)controlView;
+
+@end
+
+#endif  // CHROME_BROWSER_COCOA_EXTENSIONS_CHEVRON_MENU_BUTTON_CELL_H_