fix title of openfiles tree

package.json

@@ -96,7 +96,7 @@
         "c9.ide.mount": "#86c8985f34",
         "c9.ide.navigate": "#38ae100ea1",
         "c9.ide.newresource": "#981a408a7b",
-        "c9.ide.openfiles": "#358ac94915",
+        "c9.ide.openfiles": "#2ae85a9e33",
         "c9.ide.preview": "#8f87ff2f6a",
         "c9.ide.preview.browser": "#c5b9a129de",
         "c9.ide.preview.markdown": "#bc846e1562",