Fix render loop in <Modal>, clean up ref merger code

ts/components/_util.ts

@@ -1,30 +1,6 @@
-// Copyright 2019-2020 Signal Messenger, LLC
+// Copyright 2019-2021 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
-import { MutableRefObject, Ref } from 'react';
-import { isFunction } from 'lodash';
-import memoizee from 'memoizee';
-
 export function cleanId(id: string): string {
   return id.replace(/[^\u0020-\u007e\u00a0-\u00ff]/g, '_');
 }
-
-// Memoizee makes this difficult.
-// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
-export const createRefMerger = () =>
-  memoizee(
-    <T>(...refs: Array<Ref<T>>) => {
-      return (t: T) => {
-        refs.forEach(r => {
-          if (isFunction(r)) {
-            r(t);
-          } else if (r) {
-            // Using a MutableRefObject as intended
-            // eslint-disable-next-line no-param-reassign
-            (r as MutableRefObject<T>).current = t;
-          }
-        });
-      };
-    },
-    { length: false, max: 1 }
-  );