Kevin Millikin
fbb6c121e6
This allows us to represent type parameters with promoted bounds which are different from the bound at the declaration. A missing promoted bound indicates that the type parameter has the original bound at the declaration. This is a representation-only change, the optional bound is always `null`. Closes #29529. BUG=https://github.com/dart-lang/sdk/issues/29529 R=paulberry@google.com Review-Url: https://codereview.chromium.org/2866593003 .