Introduce a type of View background that stays in sync with its host

ui/views/background.h

 // Copyright (c) 2012 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 UI_VIEWS_BACKGROUND_H_
 #define UI_VIEWS_BACKGROUND_H_
 
 #include <stddef.h>
 
 #include <memory>
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "ui/native_theme/native_theme.h"
 #include "ui/views/views_export.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif  // defined(OS_WIN)
 
 namespace gfx {
 class Canvas;
 }
 
@@ skipping 15 matching lines @@
 //
 /////////////////////////////////////////////////////////////////////////////
 class VIEWS_EXPORT Background {
  public:
   Background();
   virtual ~Background();
 
   // Creates a background that fills the canvas in the specified color.
   static Background* CreateSolidBackground(SkColor color);
 
+  // Creates a background that fills the canvas in the color specified by the
+  // view's NativeTheme and the given color identifier.
+  static Background* CreateThemedSolidBackground(
+      View* view,
+      ui::NativeTheme::ColorId color_id);
+
   // Creates a background that fills the canvas in the specified color.
   static Background* CreateSolidBackground(int r, int g, int b) {
     return CreateSolidBackground(SkColorSetRGB(r, g, b));
   }
 
   // Creates a background that fills the canvas in the specified color.
   static Background* CreateSolidBackground(int r, int g, int b, int a) {
     return CreateSolidBackground(SkColorSetARGB(a, r, g, b));
   }
 
@@ skipping 18 matching lines @@
 
  private:
   SkColor color_;
 
   DISALLOW_COPY_AND_ASSIGN(Background);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_BACKGROUND_H_