This frontend flag can be used as an alternative to
-experimental-skip-non-inlinable-function-bodies that doesn’t skip
functions defining nested types. We want to keep these types as they are
used by LLDB. Other functions ares safe to skip parsing and
type-checking.
rdar://71130519
Adds a new flag "-experimental-skip-all-function-bodies" that skips
typechecking and SIL generation for all function bodies (where
possible).
`didSet` functions are still typechecked and have SIL generated as their
body is checked for the `oldValue` parameter, but are not serialized.
Parsing will generally be skipped as well, but this isn't necessarily
the case since other flags (eg. "-verify-syntax-tree") may force delayed
parsing off.
