PackWriter: Correct total delta count when reusing pack

If the CachedPack knows its delta count, we need to increment both
the totalDeltas and reusedDeltas fields of the stats object.

Change-Id: I70113609c22476ce7f1e4d9a92f486e9b0f59e44
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/PackWriter.java

@@ -587,8 +587,10 @@ public class PackWriter {
 			stats.thinPackBytes = out.length() - (headerEnd - headerStart);
 
 		for (CachedPack pack : cachedPacks) {
+			long deltaCnt = pack.getDeltaCount();
 			stats.reusedObjects += pack.getObjectCount();
-			stats.reusedDeltas += pack.getDeltaCount();
+			stats.reusedDeltas += deltaCnt;
+			stats.totalDeltas += deltaCnt;
 			reuseSupport.copyPackAsIs(out, pack);
 		}
 		writeChecksum(out);