Reapply "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 7e477d3c223e2f4dfa426f212debf90a3bf0ac94..4718171ab6e33ea0d2029acca8287c711599739f 100644
--- a/pkg/analyzer/lib/src/dart/constant/evaluation.dart
+++ b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
@@ -1358,9 +1358,9 @@ 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;
       }
@@ -1393,13 +1393,15 @@ 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;
       }
@@ -1549,8 +1551,7 @@ 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);
@@ -1558,6 +1559,9 @@ 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].