[Auth] Make anonymous sign in wait for auth to finish initializing

[sam-gc]

This fixes b/189879344

[changeset-bot]

⚠️ No Changeset found

Latest commit: 7af65ea

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[google-oss-bot]

Binary Size Report

Affected SDKs

No changes between base commit (fad44a5) and head commit (17834c9).

Test Logs

• Base (fad44a55): https://github.com/firebase/firebase-js-sdk/actions/runs/883746545
• Head (17834c9d): https://github.com/firebase/firebase-js-sdk/actions/runs/897685484

[google-oss-bot]

Size Analysis Report

Affected Products

• @firebase/auth-exp

  • signInAnonymously

    Size Table

    Type	Base (fad44a5)	Head (17834c9)	Diff
    size	30.7 kB	30.7 kB	+31 B (+0.1%)
    size-with-ext-deps	41.9 kB	42.0 kB	+31 B (+0.1%)

Test Logs

• Base (fad44a5): https://github.com/firebase/firebase-js-sdk/actions/runs/883746545
• Head (17834c9): https://github.com/firebase/firebase-js-sdk/actions/runs/897685484

[Feiyang1]

Nice! my test project have thousands of anonymous user because of it.