[NTP Snippets] Persist the set of snippets in a pref

components/ntp_snippets/ntp_snippet.h

 // Copyright 2015 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_NTP_SNIPPETS_NTP_SNIPPET_H_
 #define COMPONENTS_NTP_SNIPPETS_NTP_SNIPPET_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "url/gurl.h"
 
 namespace base {
 class DictionaryValue;
 }
 
 namespace ntp_snippets {
 
 // Stores and vend fresh content data for the NTP. This is a dumb class with no
 // smarts at all, all the logic is in the service.
 class NTPSnippet {
  public:
   // Creates a new snippet with the given URL. URL must be valid.
   NTPSnippet(const GURL& url);
 
   ~NTPSnippet();
 
   // Creates an NTPSnippet from a dictionary. Returns a null pointer if the
   // dictionary doesn't contain at least a url. The keys in the dictionary are
   // expected to be the same as the property name, with exceptions documented in
   // the property comment.
-  static scoped_ptr<NTPSnippet> NTPSnippetFromDictionary(
+  static scoped_ptr<NTPSnippet> CreateFromDictionary(
       const base::DictionaryValue& dict);
 
+  scoped_ptr<base::DictionaryValue> ToDictionary() const;
+
   // URL of the page described by this snippet.
   const GURL& url() const { return url_; }
 
   // Subtitle to identify the site the snippet is from.
   const std::string& site_title() const { return site_title_; }
   void set_site_title(const std::string& site_title) {
     site_title_ = site_title;
   }
 
   // Favicon for the site. Do not use to directly retrieve the favicon.
   const GURL& favicon_url() const { return favicon_url_; }
   void set_favicon_url(const GURL& favicon_url) { favicon_url_ = favicon_url; }
 
   // Title of the snippet.
   const std::string& title() const { return title_; }
   void set_title(const std::string& title) { title_ = title; }
 
   // Summary or relevant extract from the content.
   const std::string& snippet() const { return snippet_; }
   void set_snippet(const std::string& snippet) { snippet_ = snippet; }
 
   // Link to an image representative of the content. Do not fetch this image
-  // directly. If initialized by NTPSnippetFromDictionary() the relevant key is
-  // 'thumbnailURL'
+  // directly. If initialized by CreateFromDictionary() the relevant key is
+  // 'thumbnailUrl'
   const GURL& salient_image_url() const { return salient_image_url_; }
   void set_salient_image_url(const GURL& salient_image_url) {
     salient_image_url_ = salient_image_url;
   }
 
   // When the page pointed by this snippet was published.  If initialized by
-  // NTPSnippetFromDictionary() the relevant key is 'creationTimestampSec'
+  // CreateFromDictionary() the relevant key is 'creationTimestampSec'
   const base::Time& publish_date() const { return publish_date_; }
   void set_publish_date(const base::Time& publish_date) {
     publish_date_ = publish_date;
   }
 
   // After this expiration date this snippet should no longer be presented to
   // the user.
   const base::Time& expiry_date() const { return expiry_date_; }
   void set_expiry_date(const base::Time& expiry_date) {
     expiry_date_ = expiry_date;
   }
 
  private:
   const GURL url_;
   std::string site_title_;
   std::string title_;
   GURL favicon_url_;
   GURL salient_image_url_;
   std::string snippet_;
   base::Time publish_date_;
   base::Time expiry_date_;
 
   DISALLOW_COPY_AND_ASSIGN(NTPSnippet);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_NTP_SNIPPET_H_