[DevTools] Fix leak in InspectorDatabaseAgent.

third_party/WebKit/Source/modules/webdatabase/InspectorDatabaseAgent.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 40 matching lines @@
     static InspectorDatabaseAgent* create(Page* page)
     {
         return new InspectorDatabaseAgent(page);
     }
     ~InspectorDatabaseAgent() override;
     DECLARE_VIRTUAL_TRACE();
 
     void disable(ErrorString*) override;
     void restore() override;
     void didCommitLoadForLocalFrame(LocalFrame*) override;
+    void discardAgent() override;
 
     // Called from the front-end.
     void enable(ErrorString*) override;
     void getDatabaseTableNames(ErrorString*, const String& databaseId, OwnPtr<protocol::Array<String>>* names) override;
     void executeSQL(ErrorString*, const String& databaseId, const String& query, PassOwnPtr<ExecuteSQLCallback>) override;
 
     void didOpenDatabase(blink::Database*, const String& domain, const String& name, const String& version);
 private:
     explicit InspectorDatabaseAgent(Page*);
     void registerDatabaseOnCreation(blink::Database*);
 
     blink::Database* databaseForId(const String& databaseId);
     InspectorDatabaseResource* findByFileName(const String& fileName);
 
     Member<Page> m_page;
     typedef HeapHashMap<String, Member<InspectorDatabaseResource>> DatabaseResourcesHeapMap;
     DatabaseResourcesHeapMap m_resources;
     bool m_enabled;
 };
 
 } // namespace blink
 
 #endif // !defined(InspectorDatabaseAgent_h)