okToGiveUpImp() has been missing a ! for a long time. This loop over
wantAll() is looking for an object where wantSatisfied() returns
false, because there is no common merge base present. Unfortunately
it was missing a !, causing the loop to break and return false after
at least one want was satisified.
Bug: 301639
Change-Id: Ifdbe0b22c9cd0a9181546d090b4990d792d70c82 Signed-off-by: Shawn O. Pearce <spearce@spearce.org>