Remove unused event listener.

The only place where this event was fired has been removed.
https://crrev.com/c/1369551/ shows in site_entry.js that
the event was removed, and a search of cs for the event
turns up no results.

Change-Id: Id1b198382cfbd004c7fbd6035e2ec7cbc656e845
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1869017Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Jarryd Goodman <jarrydg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710121}

chrome/browser/resources/settings/site_settings/all_sites.js

@@ -132,14 +132,6 @@ Polymer({
           /** @type {!CustomEvent<!{item: !SiteGroup, index: number}>} */ (e);
       this.selectedItem_ = event.detail;
     });
-    this.addEventListener('site-entry-storage-updated', () => {
-      this.debounce('site-entry-storage-updated', () => {
-        if (this.sortMethods_ &&
-            this.$.sortMethod.value == settings.SortMethod.STORAGE) {
-          this.onSortMethodChanged_();
-        }
-      }, 500);
-    });
     this.sortMethod_ = this.$.sortMethod.value;
   },