Initialize and reset V4LocalDBManager. Instantiate V4Stores.

components/safe_browsing_db/v4_database.h

Index: components/safe_browsing_db/v4_database.h
diff --git a/components/safe_browsing_db/v4_database.h b/components/safe_browsing_db/v4_database.h
index 509939e68be6366928a21ca4071958d50fb574b7..26dd599d90ba1bad8da029093f56d72124c93e48 100644
--- a/components/safe_browsing_db/v4_database.h
+++ b/components/safe_browsing_db/v4_database.h
@@ -15,6 +15,9 @@ namespace safe_browsing {
 
 class V4Database;
 
+typedef base::Callback<void(std::unique_ptr<V4Database>)>
+    NewDatabaseReadyCallback;
+
 typedef const base::hash_map<UpdateListIdentifier,
                              const base::FilePath::CharType>
     ListInfoMap;
@@ -44,17 +47,17 @@ class V4DatabaseFactory {
 class V4Database {
  public:
   // Factory method for obtaining a V4Database implementation.
-  // It is not thread safe.
-  // The availability of each list is controlled by the one flag on this
-  // method.
-  static V4Database* Create(
+  // Posts a task on the provided task runner to create the object.
+  // Once the database object has been created, it schedules the callback
+  // function on the IO thread.
+  static void Create(
       const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
       const base::FilePath& base_path,
-      ListInfoMap list_info_map);
+      ListInfoMap list_info_map,
+      NewDatabaseReadyCallback callback);
 
-  V4Database(
-     const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
-     StoreMap store_map);
+  V4Database(const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
+             StoreMap store_map);
   virtual ~V4Database();
 
   // Deletes the current database and creates a new one.
@@ -67,6 +70,20 @@ class V4Database {
   }
 
  private:
+  // Factory method for obtaining a V4Database implementation.
+  // Once the database object has been created, it schedules the callback
+  // function on the IO thread.
+  static void CreateOnTaskRunner(
+      const scoped_refptr<base::SequencedTaskRunner>& db_task_runner,
+      const base::FilePath& base_path,
+      ListInfoMap list_info_map,
+      NewDatabaseReadyCallback callback);
+
+  const scoped_refptr<base::SequencedTaskRunner> db_task_runner_;
+
+  // Map of UpdateListIdentifier to the V4Store.
+  StoreMap store_map_;
+
   // The factory that controls the creation of V4Database objects.
   // This is used *only* by tests.
   static V4DatabaseFactory* factory_;