Enables passing initial properties to top level window creation

ui/aura/window_tree_host_platform.cc

Index: ui/aura/window_tree_host_platform.cc
diff --git a/ui/aura/window_tree_host_platform.cc b/ui/aura/window_tree_host_platform.cc
index 6233739abb039134a68f72c3f65f73f0801a128e..e9ecea9e09107c32dfead631de76b8a907a9332d 100644
--- a/ui/aura/window_tree_host_platform.cc
+++ b/ui/aura/window_tree_host_platform.cc
@@ -40,6 +40,7 @@ WindowTreeHost* WindowTreeHost::Create(const gfx::Rect& bounds) {
 
 WindowTreeHostPlatform::WindowTreeHostPlatform(const gfx::Rect& bounds)
     : WindowTreeHostPlatform() {
+  CreateCompositor();
 #if defined(USE_OZONE)
   window_ =
       ui::OzonePlatform::GetInstance()->CreatePlatformWindow(this, bounds);
@@ -60,7 +61,6 @@ WindowTreeHostPlatform::WindowTreeHostPlatform(
     : WindowTreeHost(std::move(window_port)),
       widget_(gfx::kNullAcceleratedWidget),
       current_cursor_(ui::kCursorNull) {
-  CreateCompositor();
 }
 
 void WindowTreeHostPlatform::SetPlatformWindow(