use emptyList in clear event

lib/Timeline.js

@@ -41,7 +41,7 @@ let Timeline = class Timeline extends lit_element_1.LitElement {
             this.clearSelectedItems();
             window.removeEventListener("click", this._clearSelectionHandler);
             const myEvent = new CustomEvent("item-selected", {
-                detail: { items: this.selectedList },
+                detail: { items: [] },
                 bubbles: true,
                 composed: true,
             });

src/Timeline.ts

@@ -599,7 +599,7 @@ class Timeline extends LitElement {
     this.clearSelectedItems();
     window.removeEventListener("click", this._clearSelectionHandler);
     const myEvent = new CustomEvent("item-selected", {
-      detail: { items: this.selectedList },
+      detail: { items: [] },
       bubbles: true,
       composed: true,
     });