Move logic from memory_mac to allocator_interception_mac.

base/allocator/allocator_interception_mac.h

Index: base/allocator/allocator_interception_mac.h
diff --git a/base/allocator/allocator_interception_mac.h b/base/allocator/allocator_interception_mac.h
new file mode 100644
index 0000000000000000000000000000000000000000..6be5210947e1f6c8e51b9654040fe03d48c0a2a7
--- /dev/null
+++ b/base/allocator/allocator_interception_mac.h
@@ -0,0 +1,23 @@
+// 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.
+
+#ifndef BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_
+#define BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_
+
+#include <stddef.h>
+
+namespace base {
+namespace allocator {
+
+// Calls the original implementation of malloc/calloc prior to interception.
+bool UncheckedMallocMac(size_t size, void** result);
+bool UncheckedCallocMac(size_t num_items, size_t size, void** result);
+
+// Intercepts calls to default and purgeable malloc zones. Intercepts Core
+// Foundation and Objective-C allocations.
+void InterceptAllocationsMac();
+}  // namespace allocator
+}  // namespace base
+
+#endif  // BASE_ALLOCATOR_ALLOCATOR_INTERCEPTION_MAC_H_