Revert "Gallery2: Set PhotoPage GL root reset when rotate"

This reverts commit 104f3678.

Change the orientation in SlideshowPage which is active,
photoPage reload the data and invalidate UI in inactive state.
This cause UI is black when return from SlideshowPage to PhotoPage.
So revert it to avoid reloading data and invalidating UI,
if PhotoPage is inactive state and the orientation change.

Change-Id: Ia60af41662c60858d92d00fcacb6686a123c0e21
CRs-Fixed: 997153