Call decStrongHandle last in BpBinder::onLastStrongRef

Move the decStrongHandle call to later in the function, after
removeFrozenStateChangeCallback. This ensures that the handle is still
valid at the time of removeFrozenStateChangeCallback.

Flag: build.RELEASE_LIBBINDER_BPBINDER_DECSTRONG_LAST
Test: atest binderLibTest
Bug: 443056917
Bug: 445041170
Cherrypick-From: https://googleplex-android-review.googlesource.com/q/commit:98d140121fc515f05970ea3bf9f361e18017b634
Merged-In: I9ed65c406f7284123545070f6df88ca941855a77
Change-Id: I9ed65c406f7284123545070f6df88ca941855a77