Removing facets individually should also show the help message if there is no more facet.

git-svn-id: http://google-refine.googlecode.com/svn/trunk@1560 7d457c2a-affb-35e4-300a-418c747d4874

main/webapp/modules/core/scripts/project/browsing-engine.js

@@ -194,6 +194,9 @@ BrowsingEngine.prototype.removeFacet = function(facet) {
     
     if (update) {
         Refine.update({ engineChanged: true });
+    } else if (this._facets.length == 0) {
+        this._elmts.help.show();
+        this._elmts.header.hide();
     }
 };