Make GetRootWindow() return a Window instead of a RootWindow.

ui/views/corewm/tooltip_aura.cc

 // Copyright 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/views/corewm/tooltip_aura.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_split.h"
 #include "ui/aura/root_window.h"
 #include "ui/base/resource/resource_bundle.h"
@@ skipping 154 matching lines @@
 }
 
 gfx::Rect TooltipAura::GetBoundsForTooltip(
     const gfx::Point& origin) const {
   DCHECK(tooltip_window_);
   gfx::Rect widget_bounds;
   // For Desktop aura we constrain the tooltip to the bounds of the Widget
   // (which comes from the RootWindow).
   if (screen_type_ == gfx::SCREEN_TYPE_NATIVE &&
       gfx::SCREEN_TYPE_NATIVE != gfx::SCREEN_TYPE_ALTERNATE) {
-    aura::RootWindow* root = tooltip_window_->GetRootWindow();
-    widget_bounds = gfx::Rect(root->GetHostOrigin(), root->GetHostSize());
+    aura::WindowEventDispatcher* dispatcher = tooltip_window_->GetDispatcher();
+    widget_bounds = gfx::Rect(dispatcher->GetHostOrigin(),
+                              dispatcher->GetHostSize());
   }
   gfx::Screen* screen = gfx::Screen::GetScreenByType(screen_type_);
   gfx::Rect bounds(screen->GetDisplayNearestPoint(origin).bounds());
   if (!widget_bounds.IsEmpty())
     bounds.Intersect(widget_bounds);
   return bounds;
 }
 
 void TooltipAura::SetTooltipBounds(const gfx::Point& mouse_pos,
                                    int tooltip_width,
@@ skipping 81 matching lines @@
 }
 
 void TooltipAura::OnWidgetDestroying(views::Widget* widget) {
   DCHECK_EQ(widget_, widget);
   widget_ = NULL;
   tooltip_window_ = NULL;
 }
 
 }  // namespace corewm
 }  // namespace views