Serializing Let requires us to serialize variable declarations which are
complicated. They require us to support optional values because they
have an optional initializer. This is done by using a _ for none.
Having support for Let will allow us to support variable get and set.
Change-Id: I207183730389de70409ae6ca5017510420e36830
Reviewed-on: https://dart-review.googlesource.com/c/88182
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
Reviewed-by: Daniel Hillerström <hillerstrom@google.com>
Commit-Queue: Kevin Millikin <kmillikin@google.com>
Kevin Millikin
66fa918fd3