refactor(transformer/arrow-functions): reduce repeated code

[overlookmotel]

Follow-on after #8024. Pure refactor. Make self.visit_statement(stmt) only get called in one place, rather than 2.

[overlookmotel]

• refactor(transformer/arrow-functions): add TODO comments #8328
• refactor(transformer/arrow-functions): reduce repeated code #8323 👈 (View in Graphite)
• perf(transformer/arrow-functions): reduce size of inlined visitor #8322
• refactor(transformer/arrow-functions): do not inline non-trivial visitor method #8321
• refactor(transformer/arrow-functions): reorder visitor methods #8320
• refactor(transformer/arrow-functions): rename lifetime #8319
• perf(transformer/arrow-functions): use NonEmptyStack instead of Stack #8318
• refactor(transformer/arrow-functions): shorten AstBuilder call #8317
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #8323 will not alter performance

_{Comparing 01-07-refactor_transformer_arrow-functions_reduce_repeated_code (73d0025) with 01-07-perf_transformer_arrow-functions_reduce_size_of_inlined_visitor (62e3f7e)}

Summary

✅ 29 untouched benchmarks

[graphite-app]

Merge activity

• Jan 7, 8:32 PM EST: A user added this pull request to the Graphite merge queue.
• Jan 7, 9:14 PM EST: A user merged this pull request with the Graphite merge queue.