Set toolbar padding to something appropriate for Metro icons.

ui/base/scale.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_BASE_SCALE_H_
+#define UI_BASE_SCALE_H_
+#pragma once
+
+#include "ui/base/ui_export.h"
+
+namespace ui {
+
+enum DisplayScale {
+  DS_ASH,

[sky, 2012/04/18 21:50:32]

These names are completely non-obvious. Please add a description.

Also, DS doesn't mean much, how about SCALE? I'm not opposed to DISPLAY_SCALE
either, but it's a bit long.

+  DS_DESKTOP_100,
+  DS_DESKTOP_200,
+  DS_METRO_100,
+  DS_METRO_140,
+  DS_METRO_180,
+};
+
+// Returns the display scale in use.
+UI_EXPORT const DisplayScale GetDisplayScale();
+
+}  // namespace ui
+
+#endif  // UI_BASE_SCALE_H_