Parse type variables of local functions before return type.

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library fasta.body_builder;
 
 import 'package:kernel/ast.dart'
     hide InvalidExpression, InvalidInitializer, InvalidStatement;
 
 import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
@@ skipping 2472 matching lines @@
 
   @override
   void endLocalFunctionDeclaration(Token token) {
     debugEvent("LocalFunctionDeclaration");
     Statement body = popStatement();
     AsyncMarker asyncModifier = pop();
     if (functionNestingLevel != 0) {
       exitLocalScope();
     }
     FormalParameters formals = pop();
-    List<TypeParameter> typeParameters = typeVariableBuildersToKernel(pop());
-    FunctionNode function = formals.addToFunction(new FunctionNode(body,
-        typeParameters: typeParameters, asyncMarker: asyncModifier)
-      ..fileOffset = formals.charOffset
-      ..fileEndOffset = token.charOffset);
     exitLocalScope();
     var declaration = pop();
     var returnType = pop();
     var hasImplicitReturnType = returnType == null;
     returnType ??= const DynamicType();
     pop(); // Modifiers.
     exitFunction();
+    List<TypeParameter> typeParameters = typeVariableBuildersToKernel(pop());
+    FunctionNode function = formals.addToFunction(new FunctionNode(body,
+        typeParameters: typeParameters, asyncMarker: asyncModifier)
+      ..fileOffset = formals.charOffset
+      ..fileEndOffset = token.charOffset);
     if (declaration is FunctionDeclaration) {
       KernelFunctionDeclaration.setHasImplicitReturnType(
           declaration, hasImplicitReturnType);
       function.returnType = returnType;
       declaration.variable.type = function.functionType;
       declaration.function = function;
       function.parent = declaration;
     } else {
       // If [declaration] isn't a [FunctionDeclaration], it must be because
       // there was a compile-time error.
@@ skipping 1281 matching lines @@
       return AsyncMarker.Async;
     } else {
       assert(identical(starToken.stringValue, "*"));
       return AsyncMarker.AsyncStar;
     }
   } else {
     return unhandled(asyncToken.lexeme, "asyncMarkerFromTokens",
         asyncToken.charOffset, null);
   }
 }