Rework the way Widget::Init works:

chrome/browser/ui/views/bubble/border_widget_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/ui/views/bubble/border_widget_win.h"
 
 #include <windows.h>
 
 #include "chrome/browser/ui/views/bubble/border_contents.h"
 
 BorderWidgetWin::BorderWidgetWin()
     : border_contents_(NULL) {
-  set_window_style(WS_POPUP);
-  set_window_ex_style(WS_EX_TOOLWINDOW | WS_EX_LAYERED);
 }
 
-void BorderWidgetWin::Init(BorderContents* border_contents, HWND owner) {
+void BorderWidgetWin::InitBorderWidgetWin(BorderContents* border_contents,
+                                          HWND owner) {
   DCHECK(!border_contents_);
   border_contents_ = border_contents;
   border_contents_->Init();
-  WidgetWin::Init(owner, gfx::Rect());
+
+  views::Widget::CreateParams params(views::Widget::CreateParams::TYPE_POPUP);
+  params.transparent = true;
+  params.parent = owner;
+  GetWidget()->Init(params);
   SetContentsView(border_contents_);
   SetWindowPos(owner, 0, 0, 0, 0,
                SWP_NOSIZE | SWP_NOMOVE | SWP_NOACTIVATE | SWP_NOREDRAW);
 }
 
 gfx::Rect BorderWidgetWin::SizeAndGetBounds(
     const gfx::Rect& position_relative_to,
     BubbleBorder::ArrowLocation arrow_location,
     const gfx::Size& contents_size) {
   // Ask the border view to calculate our bounds (and our contents').
   gfx::Rect contents_bounds;
   gfx::Rect window_bounds;
   border_contents_->SizeAndGetBounds(position_relative_to, arrow_location,
                                      false, contents_size, &contents_bounds,
                                      &window_bounds);
   SetBounds(window_bounds);
 
   // Return |contents_bounds| in screen coordinates.
   contents_bounds.Offset(window_bounds.origin());
   return contents_bounds;
 }
 
 LRESULT BorderWidgetWin::OnMouseActivate(UINT message,
                                       WPARAM w_param,
                                       LPARAM l_param) {
   // Never activate.
   return MA_NOACTIVATE;
 }