HUE-4319 [editor] Add Impala refresh dialog to assist DB list view

This also takes care of an issue where the popover didn't close when switching to the DB list in assist.

desktop/core/src/desktop/static/desktop/js/ko.hue-bindings.js

@@ -558,7 +558,13 @@
         if (visible && $element.data('popover') && ! $.contains($element.data('popover').$tip[0], event.target)) {
           hidePopover();
         }
-      }
+      };
+
+      ko.utils.domNodeDisposal.addDisposeCallback(element, function() {
+        if (visible && $element.data('popover')) {
+          hidePopover();
+        }
+      });
 
       var showPopover = function () {
         ko.renderTemplate(options.contentTemplate, viewModel, {

desktop/core/src/desktop/templates/assist.mako

@@ -726,10 +726,10 @@ from metadata.conf import has_navigator
       <span class="assist-tables-counter">(<span data-bind="text: filteredEntries().length"></span>)</span>
       <!-- ko ifnot: loading -->
       <a class="inactive-action" href="javascript:void(0)" data-bind="click: toggleSearch, css: { 'blue' : isSearchVisible }"><i class="pointer fa fa-search" title="${_('Search')}"></i></a>
-      <!-- ko if: sourceType === 'impala' && typeof databaseName !== 'undefined'-->
+      <!-- ko if: sourceType === 'impala' -->
       <a class="inactive-action" href="javascript:void(0)" data-bind="templatePopover : { contentTemplate: 'ask-for-invalidate-content', titleTemplate: 'ask-for-invalidate-title', trigger: 'click', minWidth: '320px' }"><i class="pointer fa fa-refresh" data-bind="css: { 'fa-spin blue' : loading }" title="${_('Manually refresh the table list')}"></i></a>
       <!-- /ko -->
-      <!-- ko if: sourceType !== 'impala' || typeof databaseName === 'undefined' -->
+      <!-- ko if: sourceType !== 'impala' -->
       <a class="inactive-action" href="javascript:void(0)" data-bind="click: triggerRefresh"><i class="pointer fa fa-refresh" data-bind="css: { 'fa-spin blue' : loading }" title="${_('Manually refresh the table list')}"></i></a>
       <!-- /ko -->
       <!-- /ko -->