browser: Abstract message box dialog functions into its own header file.

chrome/browser/ui/views/simple_message_box_win.cc

+// Copyright (c) 2011 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 "chrome/browser/simple_message_box.h"
+
+#include "ui/base/message_box_win.h"
+
+namespace browser {
+
+void ShowErrorBox(gfx::NativeWindow parent,
+                  const string16& title,
+                  const string16& message) {
+  UINT flags = MB_OK | MB_ICONWARNING | MB_SETFOREGROUND | MB_TOPMOST;
+  ui::MessageBox(parent, message, title, flags);
+}
+
+bool ShowYesNoBox(gfx::NativeWindow parent,
+                  const string16& title,
+                  const string16& message) {
+  UINT flags = MB_YESNO | MB_ICONWARNING | MB_SETFOREGROUND;
+  int result = ui::MessageBox(parent, message, title, flags);
+  return result == IDYES;
+}
+
+}  // namespace browser