Apply PictureInPictureParam only if it's changed

There is a race condition in the PiP that gets triggered more easily
recently. When the entering PiP animation finishes, there could be an
immediate onTaskInfoChanged requested from onPipTransitionFinished
callback.

We try to apply new PictureInPictureParams within onTaskInfoChanged, due
to a previous change (ag/18380631), the PictureInPictureParams would be
applied forcibly when there is a deferred TaskInfo. This ends up an
immediate PiP resizing right after the entering animation finishes and
causes flicker sometimes.

The underlying issue for b/232104080 is that the aspect ratio for
resizing is not get updated. We have changed how to handle size since
then and it does not seem to be the case anymore.

Fixing the race condition by applying change only if there are
meaningful diffs in the TaskInfo.

Video: http://recall/-/aaaaaabFQoRHlzixHdtY/dU5DRHER2dt0sE7gSZQ3ru
Bug: 319471015
Test: manual, follow the reproduce steps, see also video
Test: manual, make sure no regression for b/232104080
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:33eb97afd782264958a0e3886fe56cedc50d2fb1)
Merged-In: I2f1b827747818e07de4aba2763a5cac896354a61
Change-Id: I2f1b827747818e07de4aba2763a5cac896354a61
24D1-dev is based on 24Q2-release. Therefore, we merged this CL to 24D1-dev.