[MacViews] Implement colored window frames.

chrome/browser/ui/cocoa/apps/titlebar_background_view.h

+// Copyright 2015 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_APPS_TITLEBAR_BACKGROUND_VIEW_H_
+#define CHROME_BROWSER_UI_COCOA_APPS_TITLEBAR_BACKGROUND_VIEW_H_
+
+#import <Cocoa/Cocoa.h>
+
+#import "base/mac/scoped_nsobject.h"
+#include "third_party/skia/include/core/SkColor.h"
+
+// A view that paints a solid color. Used to change the title bar background.
+@interface TitlebarBackgroundView : NSView {
+ @private
+  base::scoped_nsobject<NSColor> color_;
+  base::scoped_nsobject<NSColor> inactiveColor_;
+}
+
+// Adds a TitlebarBackgroundView to the [[window contentView] superView].
++ (void)addToNSWindow:(NSWindow*)window
+          activeColor:(SkColor)activeColor
+        inactiveColor:(SkColor)inactiveColor;
+@end
+
+#endif  // CHROME_BROWSER_UI_COCOA_APPS_TITLEBAR_BACKGROUND_VIEW_H_