mash: Fix create fullscreen widget

ui/views/mus/desktop_window_tree_host_mus_unittest.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 "ui/views/mus/desktop_window_tree_host_mus.h"
 
 #include "base/debug/stack_trace.h"
 
 #include "base/memory/ptr_util.h"
 #include "ui/aura/client/cursor_client.h"
@@ skipping 309 matching lines @@
   params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
   params.shadow_type = Widget::InitParams::SHADOW_TYPE_NONE;
   widget.Init(params);
   EXPECT_EQ(wm::ShadowElevation::NONE,
             widget.GetNativeView()->GetProperty(wm::kShadowElevationKey));
   EXPECT_EQ(wm::ShadowElevation::NONE,
             widget.GetNativeView()->GetHost()->window()->GetProperty(
                 wm::kShadowElevationKey));
 }
 
+TEST_F(DesktopWindowTreeHostMusTest, CreateFullscreenWidget) {
+  const Widget::InitParams::Type kWidgetTypes[] = {
+      Widget::InitParams::TYPE_WINDOW,
+      Widget::InitParams::TYPE_WINDOW_FRAMELESS,
+  };
+
+  for (auto widget_type : kWidgetTypes) {
+    Widget widget;
+    Widget::InitParams params(widget_type);
+    params.show_state = ui::SHOW_STATE_FULLSCREEN;
+    params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+    widget.Init(params);
+
+    EXPECT_TRUE(widget.IsFullscreen())
+        << "Fullscreen creation failed for type=" << widget_type;
+  }
+}
+
 }  // namespace views