Adjust Class<T> parameter bounds in new Bundle APIs

So they are consistent with Parcel and allow for patterns where the
client specifies a more narrow type to perform the check while returning
or populating a list of a broader type.

Test: atest -d android.os.cts.BundleTest
Bug: b/220872166#comment3
Change-Id: Ie0d430bb0ecd7fe4ee4bbbd245e38ff2813cc4eb