V4LDM: Add check for HashPrefix match and some tests

components/safe_browsing_db/v4_local_database_manager.h

 // Copyright 2016 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 COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_
 #define COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_
 
 // A class that provides the interface between the SafeBrowsing protocol manager
 // and database that holds the downloaded updates.
 
@@ skipping 40 matching lines @@
   bool MatchCsdWhitelistUrl(const GURL& url) override;
   bool MatchMalwareIP(const std::string& ip_address) override;
   bool MatchDownloadWhitelistUrl(const GURL& url) override;
   bool MatchDownloadWhitelistString(const std::string& str) override;
   bool MatchModuleWhitelistString(const std::string& str) override;
   bool CheckResourceUrl(const GURL& url, Client* client) override;
   bool IsMalwareKillSwitchOn() override;
   bool IsCsdWhitelistKillSwitchOn() override;
 
  private:
+  // Clients queued up for checking once the database is ready.
+  struct QueuedCheck {

[Nathan Parker, 2016/08/15 19:06:41]

It'd be better to add queuing all at once in a separate CL, since I can't tell
what the full impl will be.

[Scott Hess - ex-Googler, 2016/08/15 20:57:39]

I agree.  The queued checks in the prior version felt bolted-on to me, I always
wondered if there were a better way to handle them.  That kind of thing is
probably best to handle all at once, rather than dealing with it after you've
landed a bunch of scaffolding.

[vakh (use Gerrit instead), 2016/08/17 18:23:06]

Done.

+    QueuedCheck(const ListType check_type,
+                Client* client,
+                const GURL& url,
+                const std::vector<UpdateListIdentifier>& expected_threats,
+                const base::TimeTicks& start);
+    QueuedCheck(const QueuedCheck& other);
+    ~QueuedCheck();
+    ListType check_type;
+    Client* client;
+    GURL url;
+    std::vector<UpdateListIdentifier> expected_threats;
+    base::TimeTicks start;  // When check was queued.
+  };
+
+ private:
+  friend class V4LocalDatabaseManagerTest;
+  void SetTaskRunnerForTest(
+      const scoped_refptr<base::SequencedTaskRunner>& task_runner) {
+    task_runner_ = task_runner;
+  }
+
   ~V4LocalDatabaseManager() override;
 
   // The callback called each time the protocol manager downloads updates
   // successfully.
   void UpdateRequestCompleted(
       std::unique_ptr<ParsedServerResponse> parsed_server_response);
 
   void SetupUpdateProtocolManager(
       net::URLRequestContextGetter* request_context_getter,
       const V4ProtocolConfig& config);
@@ skipping 31 matching lines @@
   // The sequenced task runner for running safe browsing database operations.
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
 
   friend class base::RefCountedThreadSafe<V4LocalDatabaseManager>;
   DISALLOW_COPY_AND_ASSIGN(V4LocalDatabaseManager);
 };  // class V4LocalDatabaseManager
 
 }  // namespace safe_browsing
 
 #endif  // COMPONENTS_SAFE_BROWSING_DB_V4_LOCAL_DATABASE_MANAGER_H_