Remove unused MouseCursorEventFilter::was_mouse_warped_

ash/display/mouse_cursor_event_filter.h

Index: ash/display/mouse_cursor_event_filter.h
diff --git a/ash/display/mouse_cursor_event_filter.h b/ash/display/mouse_cursor_event_filter.h
index 972158c47c58081825b901efa031b0ce453dd1f1..62c02cb6db39044231f608d0cdb483853fca5410 100644
--- a/ash/display/mouse_cursor_event_filter.h
+++ b/ash/display/mouse_cursor_event_filter.h
@@ -96,17 +96,11 @@ class ASH_EXPORT MouseCursorEventFilter : public ui::EventHandler,
   void GetSrcAndDstRootWindows(aura::Window** src_window,
                                aura::Window** dst_window);
 
-  void reset_was_mouse_warped_for_test() { was_mouse_warped_ = false; }
-
   bool WarpMouseCursorIfNecessaryForTest(aura::Window* target_root,
                                          const gfx::Point& point_in_screen);
 
   MouseWarpMode mouse_warp_mode_;
 
-  // This flag is used to suppress the accidental mouse warp back to the
-  // original display.
-  bool was_mouse_warped_;
-
   // The bounds for warp hole windows. |dst_indicator_bounds_| is kept
   // in the instance for testing.
   gfx::Rect src_indicator_bounds_;