[ddc] Duplicated member signature information on some classes

[nshahan]

In the compiled output, some classes have duplicated member signature information attached to them. For example, see the Iterable class in the compiled output:

class Iterable extends core.Object {
  ...
}
...
dart.setMethodSignature(Iterable, () => dart.global.Object.setPrototypeOf({
  cast: dart.gFnType(R => [core.Iterable$(R), []], R => [dart.nullable(core.Object)]),
  [$cast]: dart.gFnType(R => [core.Iterable$(R), []], R => [dart.nullable(core.Object)]),
  followedBy: dart.fnType(core.Iterable$(E), [dart.nullable(core.Object)]),
  [$followedBy]: dart.fnType(core.Iterable$(E), [dart.nullable(core.Object)]),
  map: dart.gFnType(T => [core.Iterable$(T), [dart.fnType(T, [E])]], T => [dart.nullable(core.Object)]),
  [$map]: dart.gFnType(T => [core.Iterable$(T), [dart.fnType(T, [E])]], T => [dart.nullable(core.Object)]),
  where: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  [$where]: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  whereType: dart.gFnType(T => [core.Iterable$(T), []], T => [dart.nullable(core.Object)]),
  [$whereType]: dart.gFnType(T => [core.Iterable$(T), []], T => [dart.nullable(core.Object)]),
  expand: dart.gFnType(T => [core.Iterable$(T), [dart.fnType(core.Iterable$(T), [E])]], T => [dart.nullable(core.Object)]),
  [$expand]: dart.gFnType(T => [core.Iterable$(T), [dart.fnType(core.Iterable$(T), [E])]], T => [dart.nullable(core.Object)]),
  contains: dart.fnType(core.bool, [dart.nullable(core.Object)]),
  [$contains]: dart.fnType(core.bool, [dart.nullable(core.Object)]),
  forEach: dart.fnType(dart.void, [dart.fnType(dart.void, [E])]),
  [$forEach]: dart.fnType(dart.void, [dart.fnType(dart.void, [E])]),
  reduce: dart.fnType(E, [dart.nullable(core.Object)]),
  [$reduce]: dart.fnType(E, [dart.nullable(core.Object)]),
  fold: dart.gFnType(T => [T, [T, dart.fnType(T, [T, E])]], T => [dart.nullable(core.Object)]),
  [$fold]: dart.gFnType(T => [T, [T, dart.fnType(T, [T, E])]], T => [dart.nullable(core.Object)]),
  every: dart.fnType(core.bool, [dart.fnType(core.bool, [E])]),
  [$every]: dart.fnType(core.bool, [dart.fnType(core.bool, [E])]),
  join: dart.fnType(core.String, [], [core.String]),
  [$join]: dart.fnType(core.String, [], [core.String]),
  any: dart.fnType(core.bool, [dart.fnType(core.bool, [E])]),
  [$any]: dart.fnType(core.bool, [dart.fnType(core.bool, [E])]),
  toList: dart.fnType(core.List$(E), [], {growable: core.bool}, {}),
  [$toList]: dart.fnType(core.List$(E), [], {growable: core.bool}, {}),
  toSet: dart.fnType(core.Set$(E), []),
  [$toSet]: dart.fnType(core.Set$(E), []),
  take: dart.fnType(core.Iterable$(E), [core.int]),
  [$take]: dart.fnType(core.Iterable$(E), [core.int]),
  takeWhile: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  [$takeWhile]: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  skip: dart.fnType(core.Iterable$(E), [core.int]),
  [$skip]: dart.fnType(core.Iterable$(E), [core.int]),
  skipWhile: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  [$skipWhile]: dart.fnType(core.Iterable$(E), [dart.fnType(core.bool, [E])]),
  firstWhere: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  [$firstWhere]: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  lastWhere: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  [$lastWhere]: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  singleWhere: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  [$singleWhere]: dart.fnType(E, [dart.fnType(core.bool, [E])], {orElse: dart.nullable(core.Object)}, {}),
  elementAt: dart.fnType(E, [core.int]),
  [$elementAt]: dart.fnType(E, [core.int])
}, dart.getMethods(dart.global.Object.getPrototypeOf(Iterable))));

Each method has the same signature added twice, once with just a name and once with a "symbolized" name. I couldn't remove either of them without some tests failing so there must be some inconsistency in how we access the signatures at runtime.

Not all classes exhibit this pattern. Most have either just a name or just a symbol. It looks like the duplication was added long ago in the analyzer based version and it persisted when ported to kernel 749d298.

With the new runtime type system this issue also appears with the default type arguments for the instance methods that have type parameters. In order to be consistent with the method signature I had to duplicate them in the same way to get all of the lookups to work at runtime.