Introdcue AshWindowTreeHost and move ash/chrome specific code in WTH to ash.

ash/display/cursor_window_controller.cc

Index: ash/display/cursor_window_controller.cc
diff --git a/ash/display/cursor_window_controller.cc b/ash/display/cursor_window_controller.cc
index d79f5c55eaf4ca329c5e51b4d78265e4c9841c1e..5a992bf7ac9502654eff76dc9f5ac8adf4d41b9a 100644
--- a/ash/display/cursor_window_controller.cc
+++ b/ash/display/cursor_window_controller.cc
@@ -117,9 +117,10 @@ void CursorWindowController::UpdateContainer() {
   if (is_cursor_compositing_enabled_) {
     SetDisplay(display_);
   } else {
-    aura::WindowTreeHost* mirror_host = Shell::GetInstance()->
-        display_controller()->mirror_window_controller()->host();
-    SetContainer(mirror_host ? mirror_host->window() : NULL);
+    SetContainer(Shell::GetInstance()
+                     ->display_controller()

[Ben Goodger (Google), 2014/04/09 22:41:49]

nit: I think you're supposed to put the -> on the prev line.

[oshima, 2014/04/09 23:52:15]

Done. 

FYI: This is what "git cl format" does.

+                     ->mirror_window_controller()
+                     ->GetWindow());
   }
 }