Don't auto follow non-annotated tags in fetch

When fetch TagOpt is AUTO_FOLLOW do not follow refs/tags/ names that
point directly to commits which are on unreleated side branches.

Change-Id: Iea6eee5a05ae7402a7f256fd9c1e3d3b5ccb58dd
Reported-by: Slawomir Ginter <sginter@atlassian.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/transport/FetchProcess.java

@@ -164,8 +164,10 @@ class FetchProcess {
 				have.addAll(askFor.keySet());
 				askFor.clear();
 				for (final Ref r : additionalTags) {
-					final ObjectId id = r.getPeeledObjectId();
-					if (id == null || transport.local.hasObject(id))
+					ObjectId id = r.getPeeledObjectId();
+					if (id == null)
+						id = r.getObjectId();
+					if (transport.local.hasObject(id))
 						wantTag(r);
 				}
 
@@ -347,14 +349,22 @@ class FetchProcess {
 		for (final Ref r : conn.getRefs()) {
 			if (!isTag(r))
 				continue;
+
+			Ref local = haveRefs.get(r.getName());
+			ObjectId obj = r.getObjectId();
+
 			if (r.getPeeledObjectId() == null) {
-				additionalTags.add(r);
+				if (local != null && obj.equals(local.getObjectId()))
+					continue;
+				if (askFor.containsKey(obj) || transport.local.hasObject(obj))
+					wantTag(r);
+				else
+					additionalTags.add(r);
 				continue;
 			}
 
-			final Ref local = haveRefs.get(r.getName());
 			if (local != null) {
-				if (!r.getObjectId().equals(local.getObjectId()))
+				if (!obj.equals(local.getObjectId()))
 					wantTag(r);
 			} else if (askFor.containsKey(r.getPeeledObjectId())
 					|| transport.local.hasObject(r.getPeeledObjectId()))