Correctly update the popup window position

ui/aura/window.cc

 // Copyright (c) 2012 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/aura/window.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 295 matching lines @@
     SetBoundsInternal(final_bounds);
   }
 }
 
 void Window::SetBoundsInScreen(const gfx::Rect& new_bounds_in_screen,
                                const display::Display& dst_display) {
   Window* root = GetRootWindow();
   if (root) {
     aura::client::ScreenPositionClient* screen_position_client =
         aura::client::GetScreenPositionClient(root);
-    screen_position_client->SetBounds(this, new_bounds_in_screen, dst_display);
-    return;
+    if (screen_position_client) {
+      screen_position_client->SetBounds(this, new_bounds_in_screen,
+                                        dst_display);
+      return;
+    }
   }
   SetBounds(new_bounds_in_screen);
 }
 
 gfx::Rect Window::GetTargetBounds() const {
   return layer() ? layer()->GetTargetBounds() : bounds();
 }
 
 void Window::SchedulePaintInRect(const gfx::Rect& rect) {
   layer()->SchedulePaint(rect);
@@ skipping 787 matching lines @@
     layer_name = "Unnamed Window";
 
   if (id_ != -1)
     layer_name += " " + base::IntToString(id_);
 
   layer()->set_name(layer_name);
 #endif
 }
 
 }  // namespace aura