Always use SizeSpecDefaultImpl on TV

The SizeSpecLargeScreenOptimizedImpl makes the PiP too big for TV. This
CL switches TVs to using the old SizeSpecDefaultImpl.

We use a runtime check rather than flipping the flag off to avoid wrong
set up in error states, when the default (true) value is returned from
the flag check.

Bug: 275555661
Test: m && flash && start Pip and see that it is normal-sized
Change-Id: If8761cb6261f6daf2a1289a8e79e1ccc0b03b8d1