Block on Auth synchronously

[schmidt-sebastian]

Hey there! So you want to contribute to a Firebase SDK?
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Discussion

• Read the contribution guidelines (CONTRIBUTING.md).
• If this has been discussed in an issue, make sure to link to the issue here.
  If not, go file an issue about this before creating a pull request to discuss.

Testing

• Make sure all existing tests in the repository pass after your change.
• If you fixed a bug or added a feature, add a new test to cover your code.

API Changes

• At this time we cannot accept changes that affect the public API. If you'd like to help
  us make Firebase APIs better, please propose your change in an issue so that we
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[changeset-bot]

⚠️ No Changeset found

Latest commit: 7eece30

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[google-oss-bot]

Size Analysis Report

Affected Products

No changes between base commit (4c4b6ae) and head commit (9df7d60).

Test Logs

• Base (4c4b6ae): https://github.com/firebase/firebase-js-sdk/actions/runs/923415179
• Head (9df7d60): https://github.com/firebase/firebase-js-sdk/actions/runs/925972344

[google-oss-bot]

Binary Size Report

Affected SDKs

• @firebase/firestore

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	284 kB	284 kB	-248 B (-0.1%)
  esm2017	227 kB	226 kB	-208 B (-0.1%)
  main	531 kB	531 kB	-517 B (-0.1%)
  module	284 kB	284 kB	-248 B (-0.1%)
  react-native	227 kB	227 kB	-208 B (-0.1%)

• @firebase/firestore-exp

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	224 kB	224 kB	-208 B (-0.1%)
  main	511 kB	510 kB	-517 B (-0.1%)
  module	224 kB	224 kB	-208 B (-0.1%)
  react-native	224 kB	224 kB	-208 B (-0.1%)

• @firebase/firestore-lite

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	72.7 kB	72.5 kB	-204 B (-0.3%)
  main	149 kB	149 kB	-517 B (-0.3%)
  module	72.7 kB	72.5 kB	-204 B (-0.3%)
  react-native	72.9 kB	72.7 kB	-204 B (-0.3%)

• @firebase/firestore/bundle

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	290 kB	290 kB	-248 B (-0.1%)
  esm2017	177 kB	177 kB	-208 B (-0.1%)
  main	527 kB	527 kB	-517 B (-0.1%)
  module	290 kB	290 kB	-248 B (-0.1%)
  react-native	177 kB	177 kB	-208 B (-0.1%)

• @firebase/firestore/memory

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	217 kB	216 kB	-248 B (-0.1%)
  esm2017	172 kB	172 kB	-208 B (-0.1%)
  main	325 kB	325 kB	-435 B (-0.1%)
  module	217 kB	216 kB	-248 B (-0.1%)
  react-native	172 kB	172 kB	-208 B (-0.1%)

• @firebase/firestore/memory-bundle

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  browser	225 kB	224 kB	-248 B (-0.1%)
  esm2017	177 kB	177 kB	-208 B (-0.1%)
  main	322 kB	322 kB	-435 B (-0.1%)
  module	225 kB	224 kB	-248 B (-0.1%)
  react-native	177 kB	177 kB	-208 B (-0.1%)

• firebase

  Type	Base (4c4b6ae)	Head (9df7d60)	Diff
  firebase-firestore.js	335 kB	335 kB	-247 B (-0.1%)
  firebase-firestore.memory.js	270 kB	270 kB	-247 B (-0.1%)
  firebase.js	891 kB	891 kB	-247 B (-0.0%)

Test Logs

• Base (4c4b6aed): https://github.com/firebase/firebase-js-sdk/actions/runs/923415179
• Head (9df7d609): https://github.com/firebase/firebase-js-sdk/actions/runs/925972344