Float32Array needs constructors

[DartBot]

This issue was originally filed by [email protected]

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Float32Array in the DOM is currently missing its constructors.

I think we probably want to have 3 constructors.

// construct new Float32Array initialized to zeroes with given length
Float32Array(int length);

// construct a new Float32Array, initialized with the values from the supplied list.
Float32Array.fromList(List<num> values);

// construct a new Float32Array initialized with the contents of another ArrayBuffer
Float32Array.fromBuffer(ArrayBuffer buffer);

[DartBot]

This comment was originally written by [email protected]

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Set owner to @jacob314.
Removed Priority-Medium label.
Added Priority-High label.

[DartBot]

This comment was originally written by [email protected]

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This also needs to appear in dart:html.

[nex3]

Fixed by r3582.

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Set owner to @nex3.
Added Fixed label.