Remove IsDIPEnabled from Screen

ash/display/screen_ash.cc

Index: ash/display/screen_ash.cc
diff --git a/ash/display/screen_ash.cc b/ash/display/screen_ash.cc
index 125ef82a9c2cd9f198ac1c72932d8503f52970cb..8c72e1dceb37d4ca820e5ec333a7c9bed5157dca 100644
--- a/ash/display/screen_ash.cc
+++ b/ash/display/screen_ash.cc
@@ -71,9 +71,6 @@ class ScreenForShutdown : public gfx::Screen {
   }
 
   // gfx::Screen overrides:
-  virtual bool IsDIPEnabled() override {
-    return true;
-  }
   virtual gfx::Point GetCursorScreenPoint() override {
     return gfx::Point();
   }
@@ -204,10 +201,6 @@ void ScreenAsh::NotifyDisplayRemoved(const gfx::Display& display) {
       gfx::DisplayObserver, observers_, OnDisplayRemoved(display));
 }
 
-bool ScreenAsh::IsDIPEnabled() {
-  return true;
-}
-
 gfx::Point ScreenAsh::GetCursorScreenPoint() {
   return aura::Env::GetInstance()->last_mouse_location();
 }