Change Colors.fromARGB() to Colors.fromRGBA()

[dvdwasibi]

This is a potential usability improvement.

• Usually when designers/developers specify color, the order is RGBA.
• This is also true for CSS.
• Alpha value is also usually from 0-100 or 0.0-1.0 instead from 0-255.
• This will reduce cognitive overhead for designers/developers coming from the web world.

Examples:
Chrome:

Sketch:

[sethladd]

Thanks for filing! Dupe of #5205 :)

[github-actions]

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