Add module for counting date-last-roll-call and persisting those counts

components/update_client/configurator.h

 // Copyright 2014 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_UPDATE_CLIENT_CONFIGURATOR_H_
 #define COMPONENTS_UPDATE_CLIENT_CONFIGURATOR_H_
 
 #include <string>
 #include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 
 class GURL;
+class PrefService;
 
 namespace base {
 class SequencedTaskRunner;
 class Version;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
@@ skipping 79 matching lines @@
   // non on-demand components.
   virtual bool UseBackgroundDownloader() const = 0;
 
   // True if signing of update checks is enabled.
   virtual bool UseCupSigning() const = 0;
 
   // Gets a task runner to a blocking pool of threads suitable for worker jobs.
   virtual scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner()
       const = 0;
 
+  // Returns a PrefService that the update_client can use to store persistent
+  // update information. The PrefService must outlive the entire update_client,
+  // and be safe to access from the thread the update_client is constructed
+  // on.
+  // Returning NULL is safe and will disable any functionality that requires

[Bernhard Bauer, 2016/04/08 09:06:09]

Nit: Now that the NULL #define is deprecated, I would use "null" for the
conceptual null value (which we implement in code with `nullptr`).

[waffles, 2016/04/08 19:11:00]

Done.

+  // persistent storage.
+  virtual PrefService* GetPrefService() const = 0;
+
  protected:
   friend class base::RefCountedThreadSafe<Configurator>;
 
   virtual ~Configurator() {}
 };
 
 }  // namespace update_client
 
 #endif  // COMPONENTS_UPDATE_CLIENT_CONFIGURATOR_H_