import: fix parent selection when importing merges With "wp1" and "wp2" the current working directory parents, "p1" and "p2" the patch parents and "parents" the resulting commit parents, the current behaviour is: --bypass --exact p2 parents 0 0 0 [wp1, wp2] 0 0 1 [wp1, wp2]/buggy 0 1 0 [p1] 0 1 1 [p1, p2] 1 0 0 [wp1, wp2] 1 0 1 [p1, p2] 1 1 0 [p1] 1 1 1 [p1, p2] The original behaviour before f53dc0787424 was: --bypass --exact p2 parents 0 0 0 [wp1, wp2] 0 0 1 if p1 == wp1 then [p1, p2] otherwise [wp1, wp2] 0 1 0 [p1] 0 1 1 [p1, p2] This patch restores the previous behaviour when --bypass is not set, and align --bypass behaviour when --exact is not set with merge diffs.