Fix Servercache bug

[maneesht]

Initialized serverCache to undefined until an operation is applied, and used that to prevent unknown deep merges.

[changeset-bot]

🦋 Changeset detected

Latest commit: 8695218

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@firebase/database	Patch
@firebase/database-compat	Patch
firebase	Patch

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[google-oss-bot]

Size Report ¹

Affected Products

• @firebase/database

  Type	Base (4604b3c)	Merge (d95a390)	Diff
  browser	248 kB	248 kB	+23 B (+0.0%)
  esm5	276 kB	276 kB	+23 B (+0.0%)
  main	281 kB	281 kB	+23 B (+0.0%)
  module	248 kB	248 kB	+23 B (+0.0%)

• @firebase/database-compat/standalone

  Type	Base (4604b3c)	Merge (d95a390)	Diff
  main	370 kB	370 kB	+23 B (+0.0%)

• bundle

  Type	Base (4604b3c)	Merge (d95a390)	Diff
  database (Append to a list of data)	148 kB	148 kB	+8 B (+0.0%)
  database (Filtering data)	147 kB	147 kB	+8 B (+0.0%)
  database (Listen for child events)	163 kB	164 kB	+5 B (+0.0%)
  database (Listen for value events + Detach listeners)	163 kB	163 kB	+5 B (+0.0%)
  database (Listen for value events)	163 kB	163 kB	+5 B (+0.0%)
  database (Read data once)	163 kB	163 kB	+9 B (+0.0%)
  database (Save data as transactions)	165 kB	165 kB	+5 B (+0.0%)
  database (Sort data)	149 kB	149 kB	+8 B (+0.0%)
  database (Write data)	147 kB	147 kB	+8 B (+0.0%)

• firebase

  Type	Base (4604b3c)	Merge (d95a390)	Diff
  firebase-compat.js	746 kB	746 kB	+2 B (+0.0%)
  firebase-database-compat.js	166 kB	166 kB	+2 B (+0.0%)
  firebase-database.js	154 kB	154 kB	+2 B (+0.0%)

Test Logs

• Base (4604b3c): https://github.com/firebase/firebase-js-sdk/actions/runs/3998888945
• Merge (d95a390): https://github.com/firebase/firebase-js-sdk/actions/runs/3999923064

1. https://storage.googleapis.com/firebase-sdk-metric-reports/VGFIugsaq7.html

[google-oss-bot]

Size Analysis Report ¹

This report is too large (99,544 characters) to be displayed here in a GitHub comment. Please use the below link to see the full report on Google Cloud Storage.

Test Logs

• Base (4604b3c): https://github.com/firebase/firebase-js-sdk/actions/runs/3998888945
• Merge (0d244a4): https://github.com/firebase/firebase-js-sdk/actions/runs/3999887213

1. https://storage.googleapis.com/firebase-sdk-metric-reports/6OtPxIZ8ao.html