Revert "Roll engine to pick up fix for windows preview-dart-2 tests"
Revert "Roll engine to pick up fix for windows preview-dart-2 tests"

This reverts commit dbd3eb678af12bf0e91a289dba4a400d05e523e0.

Commit above fixed initial problem with frontend_server on Windows, but caused another more explicit problem with gen_snapshot down the line.

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