Split global consistency checks from the per-group sanity checks

For the NoteDb migration, we are more interested in the former
problems, and it is unclear if our bulk migration tooling has the
capacity to contact arbitrary group backends.

Change-Id: I49eac82fb75a0e94148d262a76e82e97a1d3eb8d

java/com/google/gerrit/extensions/api/config/ConsistencyCheckInfo.java

@@ -78,5 +78,13 @@ public class ConsistencyCheckInfo {
     public String toString() {
       return status.name() + ": " + message;
     }
+
+    public static ConsistencyProblemInfo warning(String fmt, Object... args) {
+      return new ConsistencyProblemInfo(Status.WARNING, String.format(fmt, args));
+    }
+
+    public static ConsistencyProblemInfo error(String fmt, Object... args) {
+      return new ConsistencyProblemInfo(Status.ERROR, String.format(fmt, args));
+    }
   }
 }