SurfaceControlViewHost: Always set FLAG_HARDWARE_ACCELERATED for embedded views

If FLAG_HARDWARE_ACCELERATED is not set, view
framework will not use hw rendering and the shadows
will not be rendered.

Fix this by adding the flag when setting the view in
SurfaceControlViewHost. The public api already sets this
flag, so this brings parity to the internal api as well.

Test: Embedded window can draw shadows
Fixes: 180613222
Change-Id: Ife84ea9e09d415679fdf973bbc572eda360921e4