Add support for generic function type syntax, part 1

pkg/analyzer/lib/dart/ast/visitor.dart

Index: pkg/analyzer/lib/dart/ast/visitor.dart
diff --git a/pkg/analyzer/lib/dart/ast/visitor.dart b/pkg/analyzer/lib/dart/ast/visitor.dart
index ad96bed8007a1dcd2b5838e37187dfb203b11ceb..310d334fddf56df30b787a7a1263ae7d3d048b38 100644
--- a/pkg/analyzer/lib/dart/ast/visitor.dart
+++ b/pkg/analyzer/lib/dart/ast/visitor.dart
@@ -336,6 +336,13 @@ class GeneralizingAstVisitor<R> implements AstVisitor<R> {
       visitNormalFormalParameter(node);
 
   @override
+  R visitGenericFunctionType(GenericFunctionType node) =>
+      visitTypeAnnotation(node);
+
+  @override
+  R visitGenericTypeAlias(GenericTypeAlias node) => visitTypeAlias(node);
+
+  @override
   R visitHideCombinator(HideCombinator node) => visitCombinator(node);
 
   R visitIdentifier(Identifier node) => visitExpression(node);
@@ -528,6 +535,8 @@ class GeneralizingAstVisitor<R> implements AstVisitor<R> {
 
   R visitTypeAlias(TypeAlias node) => visitNamedCompilationUnitMember(node);
 
+  R visitTypeAnnotation(TypeAnnotation node) => visitNode(node);
+
   @override
   R visitTypeArgumentList(TypeArgumentList node) => visitNode(node);
 
@@ -880,6 +889,18 @@ class RecursiveAstVisitor<R> implements AstVisitor<R> {
   }
 
   @override
+  R visitGenericFunctionType(GenericFunctionType node) {
+    node.visitChildren(this);
+    return null;
+  }
+
+  @override
+  R visitGenericTypeAlias(GenericTypeAlias node) {
+    node.visitChildren(this);
+    return null;
+  }
+
+  @override
   R visitHideCombinator(HideCombinator node) {
     node.visitChildren(this);
     return null;
@@ -1398,6 +1419,12 @@ class SimpleAstVisitor<R> implements AstVisitor<R> {
       null;
 
   @override
+  R visitGenericFunctionType(GenericFunctionType node) => null;
+
+  @override
+  R visitGenericTypeAlias(GenericTypeAlias node) => null;
+
+  @override
   R visitHideCombinator(HideCombinator node) => null;
 
   @override
@@ -2000,6 +2027,22 @@ class TimedAstVisitor<T> implements AstVisitor<T> {
   }
 
   @override
+  T visitGenericFunctionType(GenericFunctionType node) {
+    stopwatch.start();
+    T result = _baseVisitor.visitGenericFunctionType(node);
+    stopwatch.stop();
+    return result;
+  }
+
+  @override
+  T visitGenericTypeAlias(GenericTypeAlias node) {
+    stopwatch.start();
+    T result = _baseVisitor.visitGenericTypeAlias(node);
+    stopwatch.stop();
+    return result;
+  }
+
+  @override
   T visitHideCombinator(HideCombinator node) {
     stopwatch.start();
     T result = _baseVisitor.visitHideCombinator(node);
@@ -2642,6 +2685,12 @@ class UnifyingAstVisitor<R> implements AstVisitor<R> {
       visitNode(node);
 
   @override
+  R visitGenericFunctionType(GenericFunctionType node) => visitNode(node);
+
+  @override
+  R visitGenericTypeAlias(GenericTypeAlias node) => visitNode(node);
+
+  @override
   R visitHideCombinator(HideCombinator node) => visitNode(node);
 
   @override