Fixed error case to return error.

git-svn-id: svn://10.0.0.236/trunk@58912 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/modules/libjar/nsJAR.cpp

@@ -150,6 +150,7 @@ nsJAR::GetEntry(const char *zipEntry, nsIZipEntry* *result)
 {
   nsZipItem item;
   PRInt32 err = mZip.GetItem(zipEntry, &item);
+  if (err != 0) return NS_ERROR_FAILURE;
 
   nsJARItem* jarItem = new nsJARItem();
   if (jarItem == nsnull)