[base] Remove PointersMatch, making a separate std::equals hashmap

src/zone/zone.h

 // Copyright 2012 the V8 project 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 V8_ZONE_ZONE_H_
 #define V8_ZONE_ZONE_H_
 
 #include <limits>
 
 #include "src/base/hashmap.h"
@@ skipping 216 matching lines @@
   }
 
   void* operator new(size_t size, Zone* zone) { return zone->New(size); }
 
   void operator delete(void* pointer) { UNREACHABLE(); }
   void operator delete(void* pointer, Zone* zone) { UNREACHABLE(); }
 };
 
 typedef base::PointerTemplateHashMapImpl<ZoneAllocationPolicy> ZoneHashMap;
 
+typedef base::CustomMatcherTemplateHashMapImpl<ZoneAllocationPolicy>
+    CustomMatcherZoneHashMap;
+
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ZONE_ZONE_H_