Revert^2 "Deprecate Activity#isChild/getParent"

This reverts commit de48acfda6a83e639dffe29fd96b8b8a4657e41f.

Reason for revert: Reland for 24Q3

Change-Id: I42056f07e68b3ded2312dee29659c9bebea72eea
Fix: 318470489
2 files changed