This adds a third reference to Field declaration, so that we know have
three references, one for each use case:
1) fieldReference used for initialization; in FieldInitializer and as
the key in the InstanceConstant.fieldValues map.
2) getterReference used for reading; in InstanceGet, StaticGet and
SuperPropertyGet
3) setterReference used for writing; in InstanceSet, StaticSet and
SuperPropertySet
TEST=existing
Change-Id: I223f130e808e7f19a831c1fe5e3a4725d1bcdc3b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/203770
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Reviewed-by: Jens Johansen <jensj@google.com>
Johnni Winther
5b7968346d