Ignore the mismatched source rect hint

When the app provided source rect hint does not match the aspect ratio,
by a certain threshold, we ignore that and in turn apply content overlay
during the enter animation, to avoid size change at the end.

In button-navigation mode, some special logical's applied as to crop the
content to its shorter edge for this case, which is inconsistent and we
will address that later in a separate change set.

Video: http://recall/-/aaaaaabFQoRHlzixHdtY/d4kLspMrqb7Xsc2JtkTW0m
Flag: NONE bug fix
Bug: 338616637
Test: Enter PiP from zoomed and non-zoomed video
Change-Id: I5059553cb9b6c02810e9638bfaf29dde9ab6140f