Use std::unique_ptr for base::DictionaryValue and base::ListValue's internal store.

base/trace_event/trace_event_memory_overhead.cc

 // Copyright 2015 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 "base/trace_event/trace_event_memory_overhead.h"
 
 #include <algorithm>
 
 #include "base/bits.h"
 #include "base/memory/ref_counted_memory.h"
@@ skipping 86 matching lines @@
            it.Advance()) {
         AddString(it.key());
         AddValue(it.value());
       }
     } break;
 
     case Value::TYPE_LIST: {
       const ListValue* list_value = nullptr;
       value.GetAsList(&list_value);
       Add("ListValue", sizeof(ListValue));
-      for (const Value* v : *list_value)
+      for (const auto& v : *list_value)
         AddValue(*v);
     } break;
 
     default:
       NOTREACHED();
   }
 }
 
 void TraceEventMemoryOverhead::AddSelf() {
   size_t estimated_size = sizeof(*this);
@@ skipping 29 matching lines @@
                    it.second.allocated_size_in_bytes);
     mad->AddScalar("resident_size", MemoryAllocatorDump::kUnitsBytes,
                    it.second.resident_size_in_bytes);
     mad->AddScalar(MemoryAllocatorDump::kNameObjectCount,
                    MemoryAllocatorDump::kUnitsObjects, it.second.count);
   }
 }
 
 }  // namespace trace_event
 }  // namespace base