Desktop aura: Break aura::Window::SetParent in two.

ui/aura/test/test_windows.cc

Index: ui/aura/test/test_windows.cc
diff --git a/ui/aura/test/test_windows.cc b/ui/aura/test/test_windows.cc
index 75cd53066056c5fbddb312be4d79751fbe99239e..f41a034d3319bb0728a234ff893b282530826325 100644
--- a/ui/aura/test/test_windows.cc
+++ b/ui/aura/test/test_windows.cc
@@ -52,21 +52,11 @@ Window* CreateTestWindowWithDelegateAndType(WindowDelegate* delegate,
   window->Init(ui::LAYER_TEXTURED);
   window->SetBounds(bounds);
   window->Show();
-  window->SetParent(parent);
+  parent->AddChild(window);
   window->SetProperty(aura::client::kCanMaximizeKey, true);
   return window;
 }
 
-Window* CreateTransientChild(int id, Window* parent) {
-  Window* window = new Window(NULL);
-  window->set_id(id);
-  window->SetType(aura::client::WINDOW_TYPE_NORMAL);
-  window->Init(ui::LAYER_TEXTURED);
-  window->SetParent(NULL);
-  parent->AddTransientChild(window);
-  return window;
-}
-
 template <typename T>
 bool ObjectIsAbove(T* upper, T* lower) {
   DCHECK_EQ(upper->parent(), lower->parent());