Provide quick fixes for `useDefineForClassFields` breaks

[DanielRosenwasser]

Since this targets 3.7.1, I'm going to close this bug. When class fields reaches stage 4, I'll do the final two steps.

Originally posted by @sandersn in #27644 (comment)

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Provide a quick fix to fix these breaks.

[sandersn]

Moving to 3.9 until class fields reach stage 4.