Revert 162381 - linux_aura: Fix tab dragging performance.

ui/base/x/x11_util.h

Index: ui/base/x/x11_util.h
===================================================================
--- ui/base/x/x11_util.h	(revision 162390)
+++ ui/base/x/x11_util.h	(working copy)
@@ -305,12 +305,6 @@
 // Return true if event type is MotionNotify.
 UI_EXPORT bool IsMotionEvent(XEvent* event);
 
-// Coalesce all pending motion events (touch or mouse) that are at the top of
-// the queue, and return the number eliminated, storing the last one in
-// |last_event|.
-UI_EXPORT int CoalescePendingMotionEvents(const XEvent* xev,
-                                          XEvent* last_event);
-
 // Returns the mapped button.
 int GetMappedButton(int button);