Use async function instead of explicit promises

dist/converse.js

@@ -72993,11 +72993,11 @@ var __WEBPACK_AMD_DEFINE_FACTORY__, __WEBPACK_AMD_DEFINE_ARRAY__, __WEBPACK_AMD_
           }
         },
 
-        renderOMEMOToolbarButton() {
+        async renderOMEMOToolbarButton() {
           const _converse = this.__super__._converse,
                 __ = _converse.__;
+          const support = await _converse.contactHasOMEMOSupport(this.model.get('jid'));
 
-          _converse.contactHasOMEMOSupport(this.model.get('jid')).then(support => {
           if (support) {
             const icon = this.el.querySelector('.toggle-omemo'),
                   html = tpl_toolbar_omemo(_.extend(this.model.toJSON(), {
@@ -73010,7 +73010,6 @@ var __WEBPACK_AMD_DEFINE_FACTORY__, __WEBPACK_AMD_DEFINE_ARRAY__, __WEBPACK_AMD_
               this.el.querySelector('.chat-toolbar').insertAdjacentHTML('beforeend', html);
             }
           }
-          }).catch(_.partial(_converse.log, _, Strophe.LogLevel.ERROR));
         },
 
         toggleOMEMO(ev) {

src/converse-omemo.js

@@ -447,10 +447,9 @@
                     }
                 },
 
-                renderOMEMOToolbarButton () {
-                    const { _converse } = this.__super__,
-                          { __ } = _converse;
-                    _converse.contactHasOMEMOSupport(this.model.get('jid')).then((support) => {
+                async renderOMEMOToolbarButton () {
+                    const { _converse } = this.__super__, { __ } = _converse;
+                    const support = await _converse.contactHasOMEMOSupport(this.model.get('jid'));
                     if (support) {
                         const icon = this.el.querySelector('.toggle-omemo'),
                               html = tpl_toolbar_omemo(_.extend(this.model.toJSON(), {'__': __}));
@@ -460,7 +459,6 @@
                             this.el.querySelector('.chat-toolbar').insertAdjacentHTML('beforeend', html);
                         }
                     }
-                    }).catch(_.partial(_converse.log, _, Strophe.LogLevel.ERROR));
                 },
 
                 toggleOMEMO (ev) {