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

ui/aura/window_tree_host_ozone.cc

Index: ui/aura/window_tree_host_ozone.cc
diff --git a/ui/aura/window_tree_host_ozone.cc b/ui/aura/window_tree_host_ozone.cc
index 0a01e426d787afd0929684d0d8d20434e1b9a791..6216440cc6e12ebb264c8bc43196321e283eedf4 100644
--- a/ui/aura/window_tree_host_ozone.cc
+++ b/ui/aura/window_tree_host_ozone.cc
@@ -59,20 +59,12 @@ void WindowTreeHostOzone::Show() { NOTIMPLEMENTED(); }
 
 void WindowTreeHostOzone::Hide() { NOTIMPLEMENTED(); }
 
-void WindowTreeHostOzone::ToggleFullScreen() { NOTIMPLEMENTED(); }
-
 gfx::Rect WindowTreeHostOzone::GetBounds() const { return bounds_; }
 
 void WindowTreeHostOzone::SetBounds(const gfx::Rect& bounds) {
   NOTIMPLEMENTED();
 }
 
-gfx::Insets WindowTreeHostOzone::GetInsets() const { return gfx::Insets(); }
-
-void WindowTreeHostOzone::SetInsets(const gfx::Insets& insets) {
-  NOTIMPLEMENTED();
-}
-
 gfx::Point WindowTreeHostOzone::GetLocationOnNativeScreen() const {
   return bounds_.origin();
 }
@@ -86,13 +78,6 @@ bool WindowTreeHostOzone::QueryMouseLocation(gfx::Point* location_return) {
   return false;
 }
 
-bool WindowTreeHostOzone::ConfineCursorToRootWindow() {
-  NOTIMPLEMENTED();
-  return false;
-}
-
-void WindowTreeHostOzone::UnConfineCursor() { NOTIMPLEMENTED(); }
-
 void WindowTreeHostOzone::PostNativeEvent(
     const base::NativeEvent& native_event) {
   NOTIMPLEMENTED();