views: add layout delegates

chrome/browser/ui/views/layout_utils.h

+// 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.
+
+#ifndef CHROME_BROWSER_UI_VIEWS_LAYOUT_UTILS_H_
+#define CHROME_BROWSER_UI_VIEWS_LAYOUT_UTILS_H_
+
+namespace views {
+class GridLayout;
+class View;
+}  // namespace views
+
+namespace layout_utils {
+
+// Creates a panel GridLayout for |host|. A panel layout has specific insets
+// applied to make it appropriate for use in a dialog or bubble. This function
+// sets the layout manager of |host| to the returned GridLayout.
+views::GridLayout* CreatePanelLayout(views::View* host);
+
+}  // namespace layout_utils
+
+#endif  // CHROME_BROWSER_UI_VIEWS_LAYOUT_UTILS_H_