This reverts commit 059326d49dcdf8aca1ddbe755cdb337059fe5b21 and updates the `widget-preview` command to always spawn the previewer using a local canvaskit binary. Fixes https://github.com/flutter/flutter/issues/166865
buildMode
icuDataPath
engineRevision
gen-l10n
10 < 9
10 > 09
--ignore-timeouts
flutter test