Skip first pack if avoid garbage is set and it is a garbage pack

At beginning of the OBJECT_SCAN loop, it will first check if the object
exists in the last pack, however, it forgot to avoid garbage pack for
the first iteration.

Change-Id: I8a99c0f439218d19c49cd4dae891b8cc4a57099d
Signed-off-by: Zhen Chen <czhen@google.com>

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsReader.java

@@ -332,6 +332,7 @@ public final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
 
 		OBJECT_SCAN: for (Iterator<T> it = pending.iterator(); it.hasNext();) {
 			T t = it.next();
+			if (!skipGarbagePack(lastPack)) {
 				try {
 					long p = lastPack.findOffset(this, t);
 					if (0 < p) {
@@ -342,6 +343,7 @@ public final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
 				} catch (IOException e) {
 					// Fall though and try to examine other packs.
 				}
+			}
 
 			for (int i = 0; i < packs.length; i++) {
 				if (i == lastIdx)