Linux Aura: Fix overlay shadows on notifications

ui/message_center/views/toast_contents_view.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/toast_contents_view.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 343 matching lines @@
     const std::string& notification_id,
     int button_index) {
   if (collection_)
     collection_->ClickOnNotificationButton(notification_id, button_index);
 }
 
 void ToastContentsView::CreateWidget(
     PopupAlignmentDelegate* alignment_delegate) {
   views::Widget::InitParams params(views::Widget::InitParams::TYPE_POPUP);
   params.keep_on_top = true;
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+  params.opacity = views::Widget::InitParams::OPAQUE_WINDOW;
+#else
   params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
+#endif
   params.delegate = this;
   views::Widget* widget = new views::Widget();
   alignment_delegate->ConfigureWidgetInitParamsForContainer(widget, &params);
   widget->set_focus_on_creation(false);
 
 #if defined(OS_WIN)
   // We want to ensure that this toast always goes to the native desktop,
   // not the Ash desktop (since there is already another toast contents view
   // there.
   if (!params.parent)
     params.native_widget = new views::DesktopNativeWidgetAura(widget);
 #endif
 
   widget->Init(params);
 }
 
 gfx::Rect ToastContentsView::GetClosedToastBounds(gfx::Rect bounds) {
   return gfx::Rect(bounds.x() + bounds.width() - kClosedToastWidth,
                    bounds.y(),
                    kClosedToastWidth,
                    bounds.height());
 }
 
 }  // namespace message_center