Hook up allocator shim on mac.

base/allocator/allocator_shim_override_mac_symbols.h

+// Copyright 2017 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.
+
+#ifdef BASE_ALLOCATOR_ALLOCATOR_SHIM_OVERRIDE_MAC_SYMBOLS_H_
+#error This header is meant to be included only once by allocator_shim.cc
+#endif
+#define BASE_ALLOCATOR_ALLOCATOR_SHIM_OVERRIDE_MAC_SYMBOLS_H_
+
+#include "base/allocator/allocator_interception_mac.h"
+#include "third_party/apple_apsl/malloc.h"
+
+namespace base {
+namespace allocator {
+
+void OverrideMacSymbols() {
+  MallocZoneFunctions new_functions;
+  new_functions.size = [](malloc_zone_t* zone, const void* ptr) -> size_t {
+    return ShimGetSizeEstimate(ptr);
+  };
+  new_functions.malloc = [](malloc_zone_t* zone, size_t size) -> void* {
+    return ShimMalloc(size);
+  };
+  new_functions.calloc = [](malloc_zone_t* zone, size_t n,
+                            size_t size) -> void* {
+    return ShimCalloc(n, size);
+  };
+  new_functions.valloc = [](malloc_zone_t* zone, size_t size) -> void* {
+    return ShimValloc(size);
+  };
+  new_functions.free = [](malloc_zone_t* zone, void* ptr) { ShimFree(ptr); };
+  new_functions.realloc = [](malloc_zone_t* zone, void* ptr,
+                             size_t size) -> void* {
+    return ShimRealloc(ptr, size);
+  };
+  new_functions.batch_malloc = [](struct _malloc_zone_t* zone, size_t size,
+                                  void** results,
+                                  unsigned num_requested) -> unsigned {
+    return ShimBatchMalloc(size, results, num_requested);
+  };
+  new_functions.batch_free = [](struct _malloc_zone_t* zone, void** to_be_freed,
+                                unsigned num_to_be_freed) -> void {
+    ShimBatchFree(to_be_freed, num_to_be_freed);
+  };
+  new_functions.memalign = [](malloc_zone_t* zone, size_t alignment,
+                              size_t size) -> void* {
+    return ShimMemalign(alignment, size);
+  };
+  new_functions.free_definite_size = [](malloc_zone_t* zone, void* ptr,
+                                        size_t size) {
+    ShimFreeDefiniteSize(ptr, size);
+  };
+
+  base::allocator::ReplaceFunctionsForDefaultZone(&new_functions);
+}
+
+}  // namespace allocator
+}  // namespace base