[PiP2] Only accept aspect ratio change if present

If the client is setting new PictureInPictureParams,
we should check whether a valid aspect ratio is provided.

Cause otherwise, even if we block the actual resize transition,
internal state might get updated leading to wrong bounds scales.
These are later on used if a re-entry state is being saved, and
might reflect incorrect reentry bounds.

We also make sure to clean-up any re-entry state and component related
state in PipBoundsState if the PiP task or activity are CLOSED (e.g.
after a client app crash). This is needed, since some tests, for
instance, do not go through normal PiP removal
and just force stop the test app.

Note: the regression in the BR listed was happening due to app icon
overlay being used when we swipe PiP to home, so one way to verify
is to run the test suite on forrest and check if src-rect-hint is larger
than the destination bounds,

Bug: 380535601
Flag: com.android.wm.shell.enable_pip2
Test: run android.platform.test.scenario \
	.launcher.integration_tests \
	.swipeupapptopip_tests on go/forrest

Change-Id: I40a93f79b5a1db0b2a01b88cfafe0d07374a10c1