Quota UsageTracker ASAN fix

webkit/quota/usage_tracker.h

 // Copyright (c) 2011 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 WEBKIT_QUOTA_USAGE_TRACKER_H_
 #define WEBKIT_QUOTA_USAGE_TRACKER_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 62 matching lines @@
   GlobalUsageCallbackQueue global_usage_callbacks_;
   HostUsageCallbackMap host_usage_callbacks_;
 
   base::WeakPtrFactory<UsageTracker> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(UsageTracker);
 };
 
 // This class holds per-client usage tracking information and caches per-host
 // usage data.  An instance of this class is created per client.
 class ClientUsageTracker : public SpecialStoragePolicy::Observer,
-                           public base::NonThreadSafe {
+                           public base::NonThreadSafe,
+                           public base::SupportsWeakPtr<ClientUsageTracker> {
  public:
   ClientUsageTracker(UsageTracker* tracker,
                      QuotaClient* client,
                      StorageType type,
                      SpecialStoragePolicy* special_storage_policy);
   virtual ~ClientUsageTracker();
 
   void GetGlobalUsage(const GlobalUsageCallback& callback);
   void GetHostUsage(const std::string& host, const HostUsageCallback& callback);
   void UpdateUsageCache(const GURL& origin, int64 delta);
@@ skipping 40 matching lines @@
   HostUsageCallbackMap host_usage_callbacks_;
 
   scoped_refptr<SpecialStoragePolicy> special_storage_policy_;
 
   DISALLOW_COPY_AND_ASSIGN(ClientUsageTracker);
 };
 
 }  // namespace quota
 
 #endif  // WEBKIT_QUOTA_USAGE_TRACKER_H_