Changing type of a widget for notification popups, to remove them from Win taskbar.

ui/message_center/views/message_popup_collection.cc

 // Copyright (c) 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 "ui/message_center/views/message_popup_collection.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 26 matching lines @@
     set_background(views::Background::CreateSolidBackground(0, 0, 0, 0));
 
     int seconds = kAutocloseDefaultDelaySeconds;
     if (notification->priority() > DEFAULT_PRIORITY)
       seconds = kAutocloseHighPriorityDelaySeconds;
     delay_ = base::TimeDelta::FromSeconds(seconds);
   }
 
   views::Widget* CreateWidget(gfx::NativeView parent) {
     views::Widget::InitParams params(
-        views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
+        views::Widget::InitParams::TYPE_POPUP);
     params.keep_on_top = true;
     if (parent)
       params.parent = parent;
     else
       params.top_level = true;
     params.transparent = true;
     params.delegate = this;
     views::Widget* widget = new views::Widget();
     widget->set_focus_on_creation(false);
     widget->Init(params);
@@ skipping 214 matching lines @@
       message_center_->notification_list()->MarkSinglePopupAsShown(
           iter->first, false);
       toasts_.erase(iter);
       break;
     }
   }
   UpdatePopups();
 }
 
 }  // namespace message_center