Revert "[ObjC][ARC] Don't remove autoreleaseRV/retainRV pairs if the call isn't"

This reverts commit 1f5b471b.
Causes asserts when building code with arc. See
https://bugs.chromium.org/p/chromium/issues/detail?id=1061289#c2
for a full repro. Will post a creduced repro once creduce is done
running.