project.config: update Code-Review copyCondition

Add 'has:unchanged-files'. This allows the vote to be copied if the set
of files is not changed; the contents are allowed to change [1]. This
matches the configuration used on chromium.googlesource.com/All-Projects
and matches the behavior of libvpx.

[1]: https://gerrit-review.googlesource.com/Documentation/config-labels.html#label_copyCondition

Change-Id: I4b0b0301d5b61d3c5736bbd5172e9f9f9e6db78e
diff --git a/project.config b/project.config
index aff6aff..4a57b63 100644
--- a/project.config
+++ b/project.config
@@ -65,13 +65,13 @@
 	value = +1 Looks good to me, but someone else must approve
 	value = +2 Looks good to me, approved
 	ignoreSelfApproval = true
-	copyCondition = changekind:NO_CHANGE OR changekind:NO_CODE_CHANGE OR changekind:TRIVIAL_REBASE OR is:MIN
+	copyCondition = changekind:NO_CODE_CHANGE OR changekind:TRIVIAL_REBASE OR has:unchanged-files OR is:MIN
 [label "Owners-Override"]
 	defaultValue = 0
 	value = 0 No score
 	value = +1 Looks good to me
 	function = NoBlock
-	copyCondition = changekind:NO_CHANGE OR changekind:NO_CODE_CHANGE OR changekind:TRIVIAL_REBASE OR has:unchanged-files
+	copyCondition = changekind:NO_CODE_CHANGE OR changekind:TRIVIAL_REBASE OR has:unchanged-files
 [access "refs/for/*"]
 	addPatchSet = group Registered Users
 	pushMerge = deny group Registered Users