[automerger skipped] Fix special case when appending a visibility rule to...

[automerger skipped] Fix special case when appending a visibility rule to //visibility:private. am: adb18952 -s ours am: 36656726 -s ours am: 2517fad6 -s ours am: 3b464bc9 -s ours

am skip reason: Change-Id Ibe7e953219e4660c653063e87cb08407a2cb513d with SHA-1 adb18952 is in history

Change-Id: Ia1782241918282169174eded104f2b0ba468cb08