Call start only when scroll position is actually changing.

There is unnecessary onScrollStart call in DataGridList render time.
DataGridList is reset itself when it is rendered and call scrollTo(0,0).
The scrollTo is calling doScrollStart without checking the position changes.
So, it is fires onScrollStart but there is no onScrollStop because it is not actually scrolling.

Fixing http://jira2.lgsvl.com/browse/BHV-11027 and http://hlm.lge.com/qi/browse/WEBOSLCD13-85658

DCO-1.1-Signed-Off-By: Kunmyon Choi kunmyon.choi@lge.com
Hi @KunmyonChoi, should the equality condition be checking against the negative value of either the current position (`this.x` and `this.y`) or the passed-in position (`inX` and `inY`)? I believe that currently specifying a position to scroll to, other than (0, 0), will still fire only the `onScrollStart` event, even if the position has not changed.