Add assertion for the presence of document to the recaptcha verifier (#4483)

* Add check for the presence of the DOM in recaptcha verifier

* Formatting

* Fix broken build

Author: sam-gc

packages-exp/auth-exp/index.ts

@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
-import { FirebaseApp } from '@firebase/app-exp';
+import { FirebaseApp, _getProvider } from '@firebase/app-exp';
 
 import { initializeAuth } from './src';
 import { registerAuth } from './src/core/auth/register';
@@ -65,7 +65,6 @@ import {
   UserProfile,
   PhoneInfoOptions
 } from '@firebase/auth-types-exp';
-import { _getProvider } from '@firebase/app-exp';
 
 // Public types
 export {

packages-exp/auth-exp/src/platform_browser/recaptcha/recaptcha_verifier.ts

@@ -168,6 +168,11 @@ export class RecaptchaVerifier
       this.auth,
       AuthErrorCode.ARGUMENT_ERROR
     );
+    _assert(
+      typeof document !== 'undefined',
+      this.auth,
+      AuthErrorCode.OPERATION_NOT_SUPPORTED
+    );
   }
 
   private makeTokenCallback(