Do not use assets for Ash window control button backgrounds

ash/ash_layout_constants.cc

+// Copyright 2016 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 "ash/ash_layout_constants.h"
+
+#include "base/logging.h"
+#include "ui/base/resource/material_design/material_design_controller.h"
+
+gfx::Size GetAshLayoutSize(AshLayoutSize size) {
+  const int kBrowserMaximizedCaptionButtonHeight[] = {27, 32, 36};
+  const int kBrowserMaximizedCaptionButtonWidth[] = {35, 32, 32};
+  const int kBrowserRestoredCaptionButtonHeight[] = {35, 36, 40};
+  const int kBrowserRestoredCaptionButtonWidth[] = {35, 32, 32};
+  const int kNonBrowserCaptionButtonHeight[] = {33, 33, 33};
+  const int kNonBrowserCaptionButtonWidth[] = {32, 32, 32};
+
+  const int mode = ui::MaterialDesignController::GetMode();
+  switch (size) {
+    case BROWSER_MAXIMIZED_CAPTION_BUTTON: {
+      return gfx::Size(kBrowserMaximizedCaptionButtonWidth[mode],
+                       kBrowserMaximizedCaptionButtonHeight[mode]);
+    }
+    case BROWSER_RESTORED_CAPTION_BUTTON: {
+      return gfx::Size(kBrowserRestoredCaptionButtonWidth[mode],
+                       kBrowserRestoredCaptionButtonHeight[mode]);
+    }
+    case NON_BROWSER_CAPTION_BUTTON: {
+      return gfx::Size(kNonBrowserCaptionButtonWidth[mode],
+                       kNonBrowserCaptionButtonHeight[mode]);
+    }
+  }
+
+  NOTREACHED();
+  return gfx::Size();
+}