An enum declaration in TypeScript code will be emitted into JavaScript
as a regular variable declaration, with the enum members being declared
inside an IIFE. For ngcc to support interpreting such variable
declarations as enum declarations with its members, ngcc needs to
recognize the enum declaration emit structure and extract all member
from the statements in the IIFE.
This commit extends the `ConcreteDeclaration` structure in the
`ReflectionHost` abstraction to be able to capture the enum members
on a variable declaration, as a substitute for the original
`ts.EnumDeclaration` as it existed in TypeScript code. The static
interpreter has been extended to handle the extracted enum members
as it would have done for `ts.EnumDeclaration`.
Fixes#35584
Resolves FW-2069
PR Close#36550
89c589085d