Revert 177182 - ViewTest.ChangeNativeViewHierarchyFindRoots failure

ui/views/widget/native_widget_aura.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/views/widget/native_widget_aura.h"
 
 #include "base/bind.h"
 #include "base/string_util.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/activation_client.h"
@@ skipping 118 matching lines @@
       // will be added to the same display as the parent.
       gfx::Rect bounds = gfx::Screen::GetScreenFor(parent)->
           GetDisplayNearestWindow(parent).bounds();
       window_bounds.set_origin(bounds.origin());
     }
   }
 
   if (parent) {
     parent->AddChild(window_);
   } else {
-    window_->SetDefaultParentByRootWindow(context->GetRootWindow(),
-                                          window_bounds);
+    // TODO(erg): Once I've threaded context through chrome, uncomment this
+    // check, which currently fails on the NULL == NULL case.
+    //
+    // DCHECK_NE(params.GetParent(), params.context);
+
+    // TODO(erg): Remove this NULL check once we've made everything in views
+    // actually pass us a context.
+    aura::RootWindow* root_window = context ? context->GetRootWindow() : NULL;
+    window_->SetDefaultParentByRootWindow(root_window, window_bounds);
   }
 
   // Wait to set the bounds until we have a parent. That way we can know our
   // true state/bounds (the LayoutManager may enforce a particular
   // state/bounds).
   if (IsMaximized())
     SetRestoreBounds(window_, window_bounds);
   else
     SetBounds(window_bounds);
   window_->set_ignore_events(!params.accept_events);
@@ skipping 899 matching lines @@
   return aura::Env::GetInstance()->is_mouse_button_down();
 }
 
 // static
 bool NativeWidgetPrivate::IsTouchDown() {
   return aura::Env::GetInstance()->is_touch_down();
 }
 
 }  // namespace internal
 }  // namespace views