Fix: change list shows '1' instead of '-1' for label score.

If a user votes '-1', and then another user votes '+1' for a label, the
label will be shown as a red '1' in the change list instead of red '-1'.

Change the logic of setting the label score to handle this case properly.

Bug: Issue 2125
Change-Id: Icf32c11ddcda7a40ee162ac6829015b8fd1b3988
1 file changed