Fixing support for shared element transitions from a window

Previously animation from window always ran in exit mode
causing the animation to play in the calling window surface
instead of the launching activity surface. This causes
flicker on transition end when the rendering switches to
the new activity surface.

Test: Verified with demo app
Change-Id: I07f5aa4e390fd9dab9883894ba7b780170c0e212
4 files changed