Revert "First step toward resolving generic function types" (TBR)

pkg/analyzer/lib/src/dart/ast/ast.dart

Index: pkg/analyzer/lib/src/dart/ast/ast.dart
diff --git a/pkg/analyzer/lib/src/dart/ast/ast.dart b/pkg/analyzer/lib/src/dart/ast/ast.dart
index d1c684bc943bf2bb6ec103e1fc139e05f19ef1e9..8722aa42f02c12b3752fa1e645d748459470d91f 100644
--- a/pkg/analyzer/lib/src/dart/ast/ast.dart
+++ b/pkg/analyzer/lib/src/dart/ast/ast.dart
@@ -5700,9 +5700,6 @@ class GenericFunctionTypeImpl extends TypeAnnotationImpl
    */
   FormalParameterList _parameters;
 
-  @override
-  DartType type;
-
   /**
    * Initialize a newly created generic function type.
    */
@@ -5746,6 +5743,9 @@ class GenericFunctionTypeImpl extends TypeAnnotationImpl
     _returnType = _becomeParentOf(type as AstNodeImpl);
   }
 
+  @override
+  DartType get type => null;
+
   /**
    * Return the type parameters for the function type, or `null` if the function
    * type does not have any type parameters.