Defer making skshader until we know quality (#24376)

[renyou]

Cherrypick to for an internal individual roll.

[flutter-dashboard]

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[flutter-dashboard]

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[pcsosinski]

rslgtm

[chinmaygarde]

Is this something we are going to land? @jason-simmons says this is to make a roll easier.

[renyou]

Is this something we are going to land? @jason-simmons says this is to make a roll easier.

Yes. This PR has already landed on master branch. It causes many golden changes internally. I am creating this branch so we can roll this PR into internal code base by itself.