Remove downlevelIteration from firebaseApp

[schmidt-sebastian]

This shaves off a little bit of size. It was meant to fix #4207, but is no longer needed for it. It sill saves some bytes though.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6a75603

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[google-oss-bot]

Binary Size Report

Affected SDKs

• @firebase/app

  Type	Base (9ac2093)	Head (b730f2d)	Diff
  browser	11.2 kB	10.8 kB	-353 B (-3.2%)
  esm2017	9.58 kB	9.57 kB	-12 B (-0.1%)
  lite	9.25 kB	8.88 kB	-372 B (-4.0%)
  lite-esm2017	7.88 kB	7.87 kB	-12 B (-0.2%)
  main	10.9 kB	10.6 kB	-360 B (-3.3%)
  module	11.2 kB	10.8 kB	-353 B (-3.2%)
  react-native	10.6 kB	10.3 kB	-360 B (-3.4%)

• firebase

  Type	Base (9ac2093)	Head (b730f2d)	Diff
  firebase-app.js	20.2 kB	19.9 kB	-276 B (-1.4%)
  firebase-performance-standalone.es2017.js	71.9 kB	71.9 kB	-10 B (-0.0%)
  firebase-performance-standalone.js	48.3 kB	48.0 kB	-271 B (-0.6%)
  firebase.js	854 kB	854 kB	-273 B (-0.0%)

Test Logs

• Base (9ac2093b): https://github.com/firebase/firebase-js-sdk/actions/runs/562312672
• Head (b730f2dd): https://github.com/firebase/firebase-js-sdk/actions/runs/562352580

[google-oss-bot]

Size Analysis Report

Affected Products

No changes between base commit (9ac2093) and head commit (b730f2d).

Test Logs

• Base (9ac2093): https://github.com/firebase/firebase-js-sdk/actions/runs/562312672
• Head (b730f2d): https://github.com/firebase/firebase-js-sdk/actions/runs/562352580