Initialize down event with original down y position.

Otherwise we could be issuing a list click event accidentally if the user raises their finger directly after the fake down event is produced.

library/src/se/emilsjolander/stickylistheaders/StickyListHeadersListView.java

@@ -473,7 +473,7 @@ public boolean dispatchTouchEvent(MotionEvent ev) {
                     cancelEvent.recycle();
                 }
 
-                MotionEvent downEvent = MotionEvent.obtain(ev);
+                MotionEvent downEvent = MotionEvent.obtain(ev.getDownTime(), ev.getEventTime(), ev.getAction(), ev.getX(), mDownY, ev.getMetaState());
                 downEvent.setAction(MotionEvent.ACTION_DOWN);
                 handled = mList.dispatchTouchEvent(downEvent);
                 downEvent.recycle();