Introduce TypedefEntity

pkg/compiler/lib/src/common_elements.dart

Index: pkg/compiler/lib/src/common_elements.dart
diff --git a/pkg/compiler/lib/src/common_elements.dart b/pkg/compiler/lib/src/common_elements.dart
index aed124f505b7a4492a74e21f102d7d1309ee5b4a..34f1709564560c343c5f39581b2bca1219155319 100644
--- a/pkg/compiler/lib/src/common_elements.dart
+++ b/pkg/compiler/lib/src/common_elements.dart
@@ -1334,4 +1334,8 @@ abstract class ElementEnvironment {
 
   /// Returns the metadata constants declared on [member].
   Iterable<ConstantValue> getMemberMetadata(MemberEntity member);
+
+  /// Returns the alias of a [typedef], that is, the function type it is an

[Siggi Cherem (dart-lang), 2017/07/12 18:11:13]

nit, how about:

/// Returns the function type that is an alias of a [typedef].

[Johnni Winther, 2017/07/13 09:19:18]

Done.

+  /// alias of.
+  FunctionType getTypedefAlias(TypedefEntity typedef);

[Siggi Cherem (dart-lang), 2017/07/12 18:11:14]

other name ideas:
 - getFunctionTypeOf
 - functionTypeOf
 - functionTypeOfTypedef
 - functionTypeAliasOf

[Johnni Winther, 2017/07/13 09:19:18]

Renamed to [getFunctionTypeOfTypedef].

 }