How to use the @firebase/app.SDK_VERSION function in @firebase/app

* you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import firebase from '@firebase/app';

/** The semver (www.semver.org) version of the SDK. */
export const SDK_VERSION = firebase.SDK_VERSION;

function addVersionHeader_(headers) {
    var version = typeof firebase !== 'undefined' ? firebase.SDK_VERSION : 'AppManager';
    headers['X-Firebase-Storage-Version'] = 'webjs/' + version;
}
/**

function addVersionHeader_(headers) {
    const version = typeof firebase !== 'undefined' ? firebase.SDK_VERSION : 'AppManager';
    headers['X-Firebase-Storage-Version'] = 'webjs/' + version;
}
/**

function addVersionHeader_(headers) {
    const version = typeof firebase !== 'undefined' ? firebase.SDK_VERSION : 'AppManager';
    headers['X-Firebase-Storage-Version'] = 'webjs/' + version;
}
/**

function addVersionHeader_(headers) {
    var version = typeof firebase !== 'undefined' ? firebase.SDK_VERSION : 'AppManager';
    headers['X-Firebase-Storage-Version'] = 'webjs/' + version;
}
/**

* you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import * as grpc from 'grpc';

import firebase from '@firebase/app';
const SDK_VERSION = firebase.SDK_VERSION;

const grpcVersion = require('grpc/package.json').version;

import { Token } from '../api/credentials';
import { DatabaseInfo } from '../core/database_info';
import { Connection, Stream } from '../remote/connection';
import { mapCodeFromRpcCode } from '../remote/rpc_error';
import { StreamBridge } from '../remote/stream_bridge';
import { assert } from '../util/assert';
import { FirestoreError } from '../util/error';
import * as log from '../util/log';
import { NodeCallback, nodePromise } from '../util/node_api';
import { Deferred } from '../util/promise';

const LOG_TAG = 'Connection';

export function addVersionHeader_(headers: Headers): void {
  const version =
    typeof firebase !== 'undefined' ? firebase.SDK_VERSION : 'AppManager';
  headers['X-Firebase-Storage-Version'] = 'webjs/' + version;
}