grep: do not skip unmerged entries when grepping in the working tree.
grep: do not skip unmerged entries when grepping in the working tree.

We used to skip unmerged entries, which made sense for grepping
in the cached copies, but not for grepping in the working tree.

Noticed by Johannes Sixt.

Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git