Ignore parent state when testing if a change can merge

The merge test is primarily concerned with file content merge
conflicts and not code review status.  The actual submit routines
allow submitting a child commit before its parent, enabling a batch
merge of multiple changes in a topic.  By telling the stategy the
parents are accepted they will not be walked by the MergeSorter and
the strategy should be able to consider only this change's commit.

Change-Id: I82257752cdc43a2a36851ec04b44a97ec28554c9
1 file changed