Load the native call wrapper via Thread.

runtime/vm/assembler.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_ASSEMBLER_H_
 #define VM_ASSEMBLER_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/globals.h"
@@ skipping 272 matching lines @@
   kPatchable,
   kNotPatchable,
 };
 
 
 class ObjectPoolWrapper : public ValueObject {
  public:
   intptr_t AddObject(const Object& obj,
                      Patchability patchable = kNotPatchable);
   intptr_t AddImmediate(uword imm);
-  intptr_t AddExternalLabel(const ExternalLabel* label,
-                            Patchability patchable);
 
   intptr_t FindObject(const Object& obj,
                       Patchability patchable = kNotPatchable);
   intptr_t FindImmediate(uword imm);
-  intptr_t FindExternalLabel(const ExternalLabel* label,
-                             Patchability patchable);
   intptr_t FindNativeEntry(const ExternalLabel* label,
                            Patchability patchable);
 
   RawObjectPool* MakeObjectPool();
 
  private:
   intptr_t AddObject(ObjectPool::Entry entry, Patchability patchable);
   intptr_t FindObject(ObjectPool::Entry entry, Patchability patchable);
 
   // Objects and jump targets.
@@ skipping 20 matching lines @@
 #include "vm/assembler_arm.h"
 #elif defined(TARGET_ARCH_ARM64)
 #include "vm/assembler_arm64.h"
 #elif defined(TARGET_ARCH_MIPS)
 #include "vm/assembler_mips.h"
 #else
 #error Unknown architecture.
 #endif
 
 #endif  // VM_ASSEMBLER_H_