Fix building of closure type arguments (fixes #25543).

runtime/vm/flow_graph_builder.h

 // Copyright (c) 2012, 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.
 
 #ifndef VM_FLOW_GRAPH_BUILDER_H_
 #define VM_FLOW_GRAPH_BUILDER_H_
 
 #include "platform/assert.h"
 #include "platform/globals.h"
 #include "vm/allocation.h"
@@ skipping 325 matching lines @@
   // May be called only if allocating an object of a parameterized class.
   Value* BuildInstantiatedTypeArguments(
       intptr_t token_pos,
       const TypeArguments& type_arguments);
 
   void BuildTypecheckPushArguments(
       intptr_t token_pos,
       PushArgumentInstr** push_instantiator_type_arguments);
   void BuildTypecheckArguments(intptr_t token_pos,
                                Value** instantiator_type_arguments);
-  Value* BuildInstantiator(intptr_t token_pos, const Class& instantiator_class);
+  Value* BuildInstantiator(intptr_t token_pos);
   Value* BuildInstantiatorTypeArguments(intptr_t token_pos,
                                         const Class& instantiator_class,
                                         Value* instantiator);
 
   // Perform a type check on the given value.
   AssertAssignableInstr* BuildAssertAssignable(intptr_t token_pos,
                                                Value* value,
                                                const AbstractType& dst_type,
                                                const String& dst_name);
 
@@ skipping 226 matching lines @@
   // Output parameters.
   GrowableArray<TargetEntryInstr**> true_successor_addresses_;
   GrowableArray<TargetEntryInstr**> false_successor_addresses_;
 
   intptr_t condition_token_pos_;
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_BUILDER_H_