Load the native call wrapper via Thread.

runtime/vm/assembler_arm.h

 // Copyright (c) 2013, 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_ASSEMBLER_ARM_H_
 #define VM_ASSEMBLER_ARM_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_arm.h directly; use assembler.h instead.
 #endif
@@ skipping 649 matching lines @@
 
   void Drop(intptr_t stack_elements);
 
   void RestoreCodePointer();
   void LoadPoolPointer(Register reg = PP);
 
   void LoadIsolate(Register rd);
 
   void LoadObject(Register rd, const Object& object, Condition cond = AL);
   void LoadUniqueObject(Register rd, const Object& object, Condition cond = AL);
-  void LoadExternalLabel(Register dst,
-                         const ExternalLabel* label,
-                         Patchability patchable,
-                         Condition cond = AL);
   void LoadFunctionFromCalleePool(Register dst,
                                   const Function& function,
                                   Register new_pp);
   void LoadNativeEntry(Register dst,
                        const ExternalLabel* label,
                        Patchability patchable,
                        Condition cond = AL);
   void PushObject(const Object& object);
   void CompareObject(Register rn, const Object& object);
 
@@ skipping 468 matching lines @@
                      Register new_value,
                      FieldContent old_content);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_ARM_H_