[flow] Upgrade from 0.279 -> 0.280

[everettbu]

Mirror of facebook/react#35329
Original author: poteto

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Flow 0.280 introduced stricter type checking for incompatible-type errors,
requiring additional $FlowFixMe suppressions alongside existing ones. Changes:

• Made QueuingStrategy properties optional in streams.js
• Made all properties optional in Web Animations API types (EffectTiming,
  KeyframeAnimationOptions, etc.)
• Added $FlowFixMe[incompatible-type] alongside existing suppressions in
  multiple files where Flow now reports additional type mismatches

[greptile-apps]

Greptile Overview

Greptile Summary

This PR upgrades Flow from version 0.279 to 0.280, which introduced stricter type checking for incompatible-type errors. The changes are purely mechanical and consist of:

• Flow version bump: Updated flow-bin and flow-remove-types to 0.280 in package.json
• Flow type environment reformatting: Large-scale whitespace and formatting changes to Flow type definition files (flow-typed/environments/*.js) to match Flow 0.280 style conventions (trailing commas, spacing)
• Type suppression updates: Added 133 new $FlowFixMe[incompatible-type] suppressions alongside or replacing existing $FlowFixMe[incompatible-call] suppressions across 67 source files
• Prettier configuration: Added flow-typed directory to .prettierignore since Flow syntax can't be parsed by Prettier

No functional code changes - all modifications are limited to Flow type suppressions and formatting. The suppressions address stricter type checking in Flow 0.280 for:

• DOM and Web Animations API calls (.animate(), .getAnimations(), etc.)
• Stream reader operations and blob serialization
• React hooks and effect dependency validation
• DevTools bridge and agent initialization
• Scheduler heap operations
• String coercion checks

The upgrade is consistent with the pattern established in previous Flow upgrades and maintains backward compatibility.

Confidence Score: 5/5

• This PR is safe to merge with no risk - it's a standard Flow version upgrade with mechanical type suppression updates
• This PR receives a perfect confidence score because: (1) it contains zero functional code changes - only Flow type suppressions and formatting, (2) all changes are mechanical and follow established patterns from previous Flow upgrades, (3) the suppressions are conservative, adding incompatible-type alongside existing suppressions rather than removing type safety, (4) it's a mirror of [flow] Upgrade from 0.279 -> 0.280 react/react#35329 which has been reviewed upstream, and (5) the changes are limited to addressing stricter type checking in Flow 0.280 without modifying runtime behavior
• No files require special attention

Important Files Changed

File Analysis

Filename	Score	Overview
package.json	5/5	Upgraded Flow version from 0.279 to 0.280 and related dependencies
yarn.lock	5/5	Updated lockfile with new Flow dependencies and hermes-parser version bump
flow-typed/environments/streams.js	5/5	Formatting updates to match Flow 0.280 style (trailing commas, spacing)
flow-typed/environments/dom.js	5/5	Large-scale reformatting to match Flow 0.280 style conventions
packages/react-reconciler/src/ReactFiberHooks.js	5/5	Added $FlowFixMe[incompatible-type] suppressions alongside existing ones for stricter Flow 0.280 checks
packages/react-dom-bindings/src/client/ReactFiberConfigDOM.js	5/5	Replaced $FlowFixMe[incompatible-call] with [incompatible-type] for animation and DOM API calls
packages/react-server/src/ReactFlightServer.js	5/5	Added $FlowFixMe[incompatible-type] suppressions for stricter type checking in console patching and blob serialization

[greptile-apps]

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