UI: Fix an issue where loading chip lingers if change has no tasks

Fire the 'tasks-loaded' event even when the change has no tasks as
the logic to hide the loading chip depends on it.

Change-Id: I4926a0ca7d4513622258b765a5e455fbb8ca1e6b

gr-task-plugin/gr-task-plugin.js

diff --git a/gr-task-plugin/gr-task-plugin.js b/gr-task-plugin/gr-task-plugin.js
index 52b0a9b..671aa71 100644
--- a/gr-task-plugin/gr-task-plugin.js
+++ b/gr-task-plugin/gr-task-plugin.js
@@ -142,19 +142,19 @@
 
           if (taskPluginInfo) {
             this._tasks = this._addTasks(taskPluginInfo.roots);
-            document.dispatchEvent(new CustomEvent('tasks-loaded', {
-              detail: {
-                ready_count: this._ready_count,
-                fail_count: this._fail_count,
-                invalid_count: this._invalid_count,
-                waiting_count: this._waiting_count,
-                duplicate_count: this._duplicate_count,
-                pass_count: this._pass_count,
-              },
-              composed: true, bubbles: true,
-            }));
           }
         }
+        document.dispatchEvent(new CustomEvent('tasks-loaded', {
+          detail: {
+            ready_count: this._ready_count,
+            fail_count: this._fail_count,
+            invalid_count: this._invalid_count,
+            waiting_count: this._waiting_count,
+            duplicate_count: this._duplicate_count,
+            pass_count: this._pass_count,
+          },
+          composed: true, bubbles: true,
+        }));
       }
     }).catch(e => {
       this._isPending = false;