Setup preference
Getting preference and waiting for it in Spark
Attempt at CachedPreference & BoolCachedPreference
Cleaned up implementation of (Bool)CachedPreference and implemented.
Implemented strip-whitespace preference
Cleaned up and documented
Merge branch 'master' of https://github.com/dart-lang/spark into umop-settings-strip_whitespace
Review fixes and fixed so that outline won't get stale AST values
Merge pull request #1623 from dart-lang/umop-settings-strip_whitespace

Strip whitespace preference (and CachedPreference [sub]class)