Fix RangeError if estimatedSize={0}

[usrbowe]

Description

If the estimatedSize is set to 0 (could be by accident or before the final value is calculated), the FlashList would throw

RangeError: Array size is not a small enough positive integer.

Root cause code:

flash-list/src/GridLayoutProviderWithProps.ts

Lines 128 to 136 in cb9c30f

	const estimatedItemCount = Math.max(
	3,
	Math.round(
	(this.props.horizontal
	? renderWindowSize.width
	: renderWindowSize.height) /
	(this.props.estimatedItemSize ?? this.defaultEstimatedItemSize)
	)
	);

The error is due to the using ?? instead of ||, so the estimatedItemCount would divide the renderWindowSize with 0. Then the value of estimatedItemCount would be Infinity.

This value is later passed to new instance of AverageWindow as size as Infinity.

The actual error is thrown from this line:

flash-list/src/utils/AverageWindow.ts

Lines 4 to 10 in cb9c30f

	export class AverageWindow {
	private currentAverage: number;
	private currentCount: number;
	private inputValues: (number | undefined)[];
	private nextIndex = 0;
	constructor(size: number, startValue?: number) {
	this.inputValues = new Array<number>(Math.max(1, size));

Creating new Array(Math.max(1, Infinity)) would throw the RangeError.

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Checklist

• I have added a changelog entry following the Keep a Changelog guidelines.

[usrbowe]

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