Revert "Don't block while runnable in getReferent()"

This reverts commit 1d9d3587dafb7078082b4d4058eea753c13ef94f.

Reason for revert: Likely cause of build failures like https://android-build.googleplex.com/builds/submitted/7611067/art-jit/latest/logs

Change-Id: I008de0d4b3976b8380935cd9a389c77e3b396274
1 file changed