Attempt 2 at: Fixes crash that occured because NativeViewHostAura::Detach was not

chrome/browser/ui/views/constrained_window_views.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 "chrome/browser/ui/views/constrained_window_views.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/utf_string_conversions.h"
@@ skipping 622 matching lines @@
 void ConstrainedWindowViews::FocusConstrainedWindow() {
   ConstrainedWindowTabHelper* helper =
       tab_contents_->constrained_window_tab_helper();
   if ((!helper->delegate() ||
        helper->delegate()->ShouldFocusConstrainedWindow()) &&
       widget_delegate() &&
       widget_delegate()->GetInitiallyFocusedView()) {
     widget_delegate()->GetInitiallyFocusedView()->RequestFocus();
   }
 #if defined(USE_ASH)
-  GetNativeView()->Focus();
+  // We don't necessarily have a RootWindow yet.
+  if (GetNativeView()->GetRootWindow())
+    GetNativeView()->Focus();
 #endif
 }
 
 gfx::NativeWindow ConstrainedWindowViews::GetNativeWindow() {
   return Widget::GetNativeWindow();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ConstrainedWindowViews, views::Widget overrides:
 
@@ skipping 26 matching lines @@
 
 views::internal::NativeWidgetDelegate*
     ConstrainedWindowViews::AsNativeWidgetDelegate() {
   return this;
 }
 
 int ConstrainedWindowViews::GetNonClientComponent(const gfx::Point& point) {
   // Prevent a constrained window to be moved by the user.
   return HTNOWHERE;
 }