adding unit test for bug 336501.

netwerk/test/unit/test_bug336501.js

@@ -0,0 +1,29 @@
+var Cc = Components.classes;
+var Ci = Components.interfaces;
+
+function run_test() {
+  var f =
+      Cc["@mozilla.org/file/directory_service;1"].
+      getService(Ci.nsIProperties).get("ComRegF", Ci.nsIFile);
+
+  var fis =
+      Cc["@mozilla.org/network/file-input-stream;1"].
+      createInstance(Ci.nsIFileInputStream);
+  fis.init(f, -1, -1, 0); 
+
+  var bis =
+      Cc["@mozilla.org/network/buffered-input-stream;1"].
+      createInstance(Ci.nsIBufferedInputStream);
+  bis.init(fis, 32);
+
+  var sis =
+      Cc["@mozilla.org/scriptableinputstream;1"].
+      createInstance(Ci.nsIScriptableInputStream);
+  sis.init(bis);
+
+  sis.read(45);
+  sis.close();
+
+  var data = sis.read(45);
+  do_check_eq(data.length, 0);
+}