fix perl warnings (bug 247147) patch by swalker, r=bryner

browser/themes/pinstripe/browser/jar.mn

@@ -36,5 +36,5 @@ classic.jar:
   skin/classic/browser/bookmarks/folderarrow.png            (bookmarks/folderarrow.png)
   skin/classic/browser/pref/Options.png                     (pref/Options.png)
   skin/classic/browser/pref/pref.css                        (pref/pref.css)
-  preview.png
+  ./preview.png
   

browser/themes/winstripe/browser/jar.mn

@@ -24,5 +24,5 @@ classic.jar:
         skin/classic/browser/bookmarks/Bookmarks-toolbar.png    (bookmarks/Bookmarks-toolbar.png)
         skin/classic/browser/pref/Options.png                   (pref/Options.png)
         skin/classic/browser/pref/pref.css                      (pref/pref.css)
-        icon.png
-        preview.png
+        ./icon.png
+        ./preview.png