Hook up allocator shim on mac.

base/allocator/allocator_shim_default_dispatch_to_linker_wrapped_symbols.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <malloc.h>
 
 #include "base/allocator/allocator_shim.h"
 #include "build/build_config.h"
 
 #if defined(OS_ANDROID) && __ANDROID_API__ < 17
@@ skipping 74 matching lines @@
 
 }  // namespace
 
 const AllocatorDispatch AllocatorDispatch::default_dispatch = {
     &RealMalloc,       /* alloc_function */
     &RealCalloc,       /* alloc_zero_initialized_function */
     &RealMemalign,     /* alloc_aligned_function */
     &RealRealloc,      /* realloc_function */
     &RealFree,         /* free_function */
     &RealSizeEstimate, /* get_size_estimate_function */
+    nullptr,           /* batch_malloc_function */
+    nullptr,           /* batch_free_function */
+    nullptr,           /* free_definite_size_function */
     nullptr,           /* next */
 };