Keep root_location to be in pixels and display coordinates in WS.

services/ui/ws/cursor_location_manager.h

Index: services/ui/ws/cursor_location_manager.h
diff --git a/services/ui/ws/cursor_location_manager.h b/services/ui/ws/cursor_location_manager.h
index 6096cdc5e6446f6ac78e51213b25c601694ac528..85d5a5e0f36f5972daf768d148775d19307db464 100644
--- a/services/ui/ws/cursor_location_manager.h
+++ b/services/ui/ws/cursor_location_manager.h
@@ -23,8 +23,8 @@ class CursorLocationManager {
   ~CursorLocationManager();
 
   // Sets the current cursor location to |point|. Atomically writes the location
-  // to shared memory.
-  void OnMouseCursorLocationChanged(const gfx::Point& point);
+  // to shared memory. |point| should be in screen-coord and DIP.
+  void OnMouseCursorLocationChanged(const gfx::Point& point_in_dip);
 
   // Returns a read-only handle to the shared memory which contains the global
   // mouse cursor position. Each call returns a new handle.