fix #27134, future unions in downwards generic method inference

pkg/analyzer/lib/src/generated/resolver.dart

 // Copyright (c) 2014, 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 analyzer.src.generated.resolver;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 7242 matching lines @@
   void _inferArgumentTypesFromContext(InvocationExpression node) {
     if (!strongMode) {
       // Use propagated type inference for lambdas if not in strong mode.
       _inferFunctionExpressionsParametersTypes(node.argumentList);
       return;
     }
 
     DartType contextType = node.staticInvokeType;
     if (contextType is FunctionType) {
       DartType originalType = node.function.staticType;
-      DartType returnContextType = InferenceContext.getType(node);
+      DartType returnContextType = InferenceContext.getContext(node);
       TypeSystem ts = typeSystem;
       if (returnContextType != null &&
           node.typeArguments == null &&
           originalType is FunctionType &&
           originalType.typeFormals.isNotEmpty &&
           ts is StrongTypeSystemImpl) {
         contextType = ts.inferGenericFunctionCall(typeProvider, originalType,
             DartType.EMPTY_LIST, DartType.EMPTY_LIST, returnContextType);
       }
 
@@ skipping 3897 matching lines @@
       return null;
     }
     if (identical(node.staticElement, variable)) {
       if (node.inSetterContext()) {
         result = true;
       }
     }
     return null;
   }
 }