[Enterprise Search] Migrate util and components from ent-search

x-pack/plugins/enterprise_search/public/applications/shared/use_did_update_effect/index.ts

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+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+export { useDidUpdateEffect } from './use_did_update_effect';

x-pack/plugins/enterprise_search/public/applications/shared/use_did_update_effect/use_did_update_effect.test.tsx

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+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+import React, { useState } from 'react';
+import { mount } from 'enzyme';
+
+import { EuiLink } from '@elastic/eui';
+
+import { useDidUpdateEffect } from './use_did_update_effect';
+
+const fn = jest.fn();
+
+const TestHook = ({ value }: { value: number }) => {
+  const [inputValue, setValue] = useState(value);
+  useDidUpdateEffect(fn, [inputValue]);
+  return <EuiLink onClick={() => setValue(2)} />;
+};
+
+const wrapper = mount(<TestHook value={1} />);
+
+describe('useDidUpdateEffect', () => {
+  it('should not fire function when value unchanged', () => {
+    expect(fn).not.toHaveBeenCalled();
+  });
+
+  it('should fire function when value changed', () => {
+    wrapper.find(EuiLink).simulate('click');
+    expect(fn).toHaveBeenCalled();
+  });
+});

x-pack/plugins/enterprise_search/public/applications/shared/use_did_update_effect/use_did_update_effect.tsx

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+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+/*
+ * Sometimes we don't want to fire the initial useEffect call.
+ * This custom Hook only fires after the intial render has completed.
+ */
+import { useEffect, useRef } from 'react';
+
+type TInput = string | number | object | Function | boolean | null | undefined;
+
+export const useDidUpdateEffect = (fn: Function, inputs: TInput[]) => {
+  const didMountRef = useRef(false);
+
+  useEffect(() => {
+    if (didMountRef.current) {
+      fn();
+    } else {
+      didMountRef.current = true;
+    }
+  }, inputs);
+};