Reload wallpaper when display configuration changes.

ash/test/test_user_wallpaper_delegate.cc

Index: ash/test/test_user_wallpaper_delegate.cc
diff --git a/ash/test/test_user_wallpaper_delegate.cc b/ash/test/test_user_wallpaper_delegate.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c3eb16e49b71fc89ecfb0ade6dcb0b586688435f
--- /dev/null
+++ b/ash/test/test_user_wallpaper_delegate.cc
@@ -0,0 +1,22 @@
+// Copyright 2013 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/test/test_user_wallpaper_delegate.h"
+
+namespace ash {
+namespace test {
+
+void TestUserWallpaperDelegate::UpdateWallpaper() {
+  DefaultUserWallpaperDelegate::UpdateWallpaper();
+  update_wallpaper_count_ ++;
+}
+
+int TestUserWallpaperDelegate::GetUpdateWallpaperCountAndReset() {
+  int count = update_wallpaper_count_;
+  update_wallpaper_count_ = 0;
+  return count;
+}
+
+}  // namespace test
+}  // namespace ash