Hook up allocator shim on mac.

base/allocator/allocator_shim.cc

Index: base/allocator/allocator_shim.cc
diff --git a/base/allocator/allocator_shim.cc b/base/allocator/allocator_shim.cc
index a9fc095b905e620dd8e2df9f060fd28e32629e27..0d0e7d9f070531edb02382e6779199b55a6be3bc 100644
--- a/base/allocator/allocator_shim.cc
+++ b/base/allocator/allocator_shim.cc
@@ -241,6 +241,24 @@ void ShimFree(void* address) {
   return chain_head->free_function(chain_head, address);
 }
 
+size_t ShimGetSizeEstimate(const void* address) {
+  const allocator::AllocatorDispatch* const chain_head = GetChainHead();
+  return chain_head->get_size_estimate_function(chain_head,
+                                                const_cast<void*>(address));
+}
+
+unsigned ShimBatchMalloc(size_t size, void** results, unsigned num_requested) {
+  const allocator::AllocatorDispatch* const chain_head = GetChainHead();
+  return chain_head->batch_malloc_function(chain_head, size, results,
+                                           num_requested);
+}
+
+void ShimBatchFree(void** to_be_freed, unsigned num_to_be_freed) {
+  const allocator::AllocatorDispatch* const chain_head = GetChainHead();
+  return chain_head->batch_free_function(chain_head, to_be_freed,
+                                         num_to_be_freed);
+}
+
 }  // extern "C"
 
 #if !defined(OS_WIN)
@@ -257,6 +275,8 @@ void ShimFree(void* address) {
 #elif defined(OS_WIN)
 // On Windows we use plain link-time overriding of the CRT symbols.
 #include "base/allocator/allocator_shim_override_ucrt_symbols_win.h"
+#elif defined(OS_MACOSX)
+#include "base/allocator/allocator_shim_override_mac_symbols.h"
 #else
 #include "base/allocator/allocator_shim_override_libc_symbols.h"
 #endif