Avoid NullPointerException in PlotCommit

Bug: 339289
Change-Id: Idf36f080ae6638c2bdbe11d69a4ad870851622b1
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/revplot/AbstractPlotRenderer.java

@@ -148,7 +148,7 @@ public abstract class AbstractPlotRenderer<TLane extends PlotLane, TColor> {
 			drawCommitDot(dotX, dotY, dotSize, dotSize);
 
 		int textx = Math.max(maxCenter + LANE_WIDTH / 2, dotX + dotSize) + 8;
-		int n = commit.refs == null ? 0 : commit.refs.length;
+		int n = commit.refs.length;
 		for (int i = 0; i < n; ++i) {
 			textx += drawLabel(textx + dotSize, h/2, commit.refs[i]);
 		}

org.eclipse.jgit/src/org/eclipse/jgit/revplot/PlotWalk.java

@@ -114,14 +114,13 @@ public class PlotWalk extends RevWalk {
 
 	private Ref[] getRefs(final AnyObjectId commitId) {
 		Collection<Ref> list = reverseRefMap.get(commitId);
-		Ref[] tags;
 		if (list == null)
-			tags = null;
+			return PlotCommit.NO_REFS;
 		else {
-			tags = list.toArray(new Ref[list.size()]);
+			Ref[] tags = list.toArray(new Ref[list.size()]);
 			Arrays.sort(tags, new PlotRefComparator());
+			return tags;
 		}
-		return tags;
 	}
 
 	class PlotRefComparator implements Comparator<Ref> {