Rework the way Widget::Init works:

chrome/browser/chromeos/login/user_controller_gtk.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/chromeos/login/user_controller.h"
 
 #include "views/widget/widget_gtk.h"
 
 using views::WidgetGtk;
 
 namespace chromeos {
 
 namespace {
 
 class ControlsWidget : public WidgetGtk {
  public:
-  ControlsWidget() : WidgetGtk(WidgetGtk::TYPE_WINDOW) {
+  ControlsWidget() {
   }
 
  private:
   // WidgetGtk overrides:
   virtual void OnMap(GtkWidget* widget) OVERRIDE {
     // For some reason, Controls window never gets first expose event,
     // which makes WM believe that the login screen is not ready.
     // This is a workaround to let WM show the login screen. While
     // this may allow WM to show unpainted window, we haven't seen any
     // issue (yet). We will not investigate this further because we're
     // migrating to different implemention (WebUI).
     UpdateFreezeUpdatesProperty(GTK_WINDOW(GetNativeView()),
                                 false /* remove */);
   }
 
   DISALLOW_COPY_AND_ASSIGN(ControlsWidget);
 };
 
 // Widget that notifies window manager about clicking on itself.
 // Doesn't send anything if user is selected.
 class ClickNotifyingWidget : public WidgetGtk {
  public:
   explicit ClickNotifyingWidget(UserController* controller)
-      : WidgetGtk(WidgetGtk::TYPE_WINDOW),
-        controller_(controller) {
+      : controller_(controller) {
   }
 
  private:
   gboolean OnButtonPress(GtkWidget* widget, GdkEventButton* event) {
     if (!controller_->IsUserSelected())
       controller_->SelectUserRelative(0);
 
     return WidgetGtk::OnButtonPress(widget, event);
   }
 
   UserController* controller_;
 
   DISALLOW_COPY_AND_ASSIGN(ClickNotifyingWidget);
 };
 
-WidgetGtk* InitWidget(WidgetGtk* widget, const gfx::Rect& bounds) {
-  widget->MakeTransparent();
-  widget->Init(NULL, bounds);
+views::Widget* InitWidget(views::Widget* widget, const gfx::Rect& bounds) {
+  views::Widget::CreateParams params(views::Widget::CreateParams::TYPE_WINDOW);
+  params.transparent = true;
+  params.bounds = bounds;
+  widget->Init(params);
   GdkWindow* gdk_window = widget->GetNativeView()->window;
   gdk_window_set_back_pixmap(gdk_window, NULL, false);
   return widget;
 }
 
 }  // namespace
 
 // static
 views::Widget* UserController::CreateControlsWidget(const gfx::Rect& bounds) {
   return InitWidget(new ControlsWidget(), bounds);
 }
 
 // static
 views::Widget* UserController::CreateClickNotifyingWidget(
     UserController* controller,
     const gfx::Rect& bounds) {
   return InitWidget(new ClickNotifyingWidget(controller), bounds);
 }
 
 }  // namespace