Add support for generic function type syntax, part 1

pkg/analyzer/lib/src/dart/constant/evaluation.dart

Index: pkg/analyzer/lib/src/dart/constant/evaluation.dart
diff --git a/pkg/analyzer/lib/src/dart/constant/evaluation.dart b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
index 8659dfea7e32437c0077b9f9a655d5275c05b427..4ac8ead1a536c984ded5f22d7a35232c48cfbda5 100644
--- a/pkg/analyzer/lib/src/dart/constant/evaluation.dart
+++ b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
@@ -8,6 +8,7 @@ import 'dart:collection';
 
 import 'package:analyzer/context/declared_variables.dart';
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/constant/value.dart';
@@ -29,7 +30,6 @@ import 'package:analyzer/src/generated/type_system.dart'
 import 'package:analyzer/src/generated/utilities_collection.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart' show ParameterKind;
 import 'package:analyzer/src/task/dart.dart';
-import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 
 /**
  * Helper class encapsulating the methods for evaluating constants and
@@ -1294,7 +1294,7 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
     ParameterizedType elseType = elseResult.type;
     return new DartObjectImpl.validWithUnknownValue(
         _typeSystem.getLeastUpperBound(_typeProvider, thenType, elseType)
-        as InterfaceType);
+            as InterfaceType);
   }
 
   @override
@@ -1359,9 +1359,9 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
       return null;
     }
     DartType elementType = _typeProvider.dynamicType;
-    NodeList<TypeName> typeArgs = node.typeArguments?.arguments;
+    NodeList<TypeAnnotation> typeArgs = node.typeArguments?.arguments;
     if (typeArgs?.length == 1) {
-      DartType type = visitTypeName(typeArgs[0])?.toTypeValue();
+      DartType type = visitTypeAnnotation(typeArgs[0])?.toTypeValue();
       if (type != null) {
         elementType = type;
       }
@@ -1394,13 +1394,15 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
     }
     DartType keyType = _typeProvider.dynamicType;
     DartType valueType = _typeProvider.dynamicType;
-    NodeList<TypeName> typeArgs = node.typeArguments?.arguments;
+    NodeList<TypeAnnotation> typeArgs = node.typeArguments?.arguments;
     if (typeArgs?.length == 2) {
-      DartType keyTypeCandidate = visitTypeName(typeArgs[0])?.toTypeValue();
+      DartType keyTypeCandidate =
+          visitTypeAnnotation(typeArgs[0])?.toTypeValue();
       if (keyTypeCandidate != null) {
         keyType = keyTypeCandidate;
       }
-      DartType valueTypeCandidate = visitTypeName(typeArgs[1])?.toTypeValue();
+      DartType valueTypeCandidate =
+          visitTypeAnnotation(typeArgs[1])?.toTypeValue();
       if (valueTypeCandidate != null) {
         valueType = valueTypeCandidate;
       }
@@ -1550,8 +1552,7 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
         _typeProvider.symbolType, new SymbolState(buffer.toString()));
   }
 
-  @override
-  DartObjectImpl visitTypeName(TypeName node) {
+  DartObjectImpl visitTypeAnnotation(TypeAnnotation node) {
     DartType type = evaluateType(node.type);
     if (type == null) {
       return super.visitTypeName(node);
@@ -1559,6 +1560,9 @@ class ConstantVisitor extends UnifyingAstVisitor<DartObjectImpl> {
     return typeConstant(type);
   }
 
+  @override
+  DartObjectImpl visitTypeName(TypeName node) => visitTypeAnnotation(node);
+
   /**
    * Create an error associated with the given [node]. The error will have the
    * given error [code].