Rename RootWindowHost* to WindowTreeHost*

ui/views/widget/desktop_aura/desktop_factory_ozone.h

Index: ui/views/widget/desktop_aura/desktop_factory_ozone.h
diff --git a/ui/views/widget/desktop_aura/desktop_factory_ozone.h b/ui/views/widget/desktop_aura/desktop_factory_ozone.h
index e557d3bdb7af709765c4325fa9f5b310335600bf..d2a00237190047355dfa308610f46a862f272e88 100644
--- a/ui/views/widget/desktop_aura/desktop_factory_ozone.h
+++ b/ui/views/widget/desktop_aura/desktop_factory_ozone.h
@@ -13,7 +13,7 @@ class Rect;
 
 namespace views {
 class DesktopNativeWidgetAura;
-class DesktopRootWindowHost;
+class DesktopWindowTreeHost;
 
 namespace internal {
 class NativeWidgetDelegate;
@@ -30,9 +30,9 @@ class VIEWS_EXPORT DesktopFactoryOzone {
   // Sets the implementation delegate. Ownership is retained by the caller.
   static void SetInstance(DesktopFactoryOzone* impl);
 
-  // Delegates implementation of DesktopRootWindowHost::Create externally to
+  // Delegates implementation of DesktopWindowTreeHost::Create externally to
   // Ozone implementation.
-  virtual DesktopRootWindowHost* CreateRootWindowHost(
+  virtual DesktopWindowTreeHost* CreateWindowTreeHost(
       internal::NativeWidgetDelegate* native_widget_delegate,
       DesktopNativeWidgetAura* desktop_native_widget_aura) = 0;