Support raw straight RGBA format in Image.toByteData()

[ColdPaleLight]

fix issue: flutter/flutter#86845

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[dnfield]

This change LGTM, but don't we have to update the web interfaces as well? Why didn't this fail the conformance test?

/cc @yjbanov

[ColdPaleLight]

This change LGTM, but don't we have to update the web interfaces as well? Why didn't this fail the conformance test?

I am trying to add this feature to the web. It seems that it can be implemented in CanvasKit, but it is difficult to implement in Html. I plan to file another PR to do this.

[ColdPaleLight]

Hi @dnfield @yjbanov
This is the implementation in CanvasKit：#28339.
Please review it together.

Thanks

[dnfield]

LGTM

I'd normally ask to throw an unimpelemented error for web but that patch will be landing soon anyway.