Instant App Banner logic.

chrome/browser/banners/app_banner_settings_helper.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 CHROME_BROWSER_BANNERS_APP_BANNER_SETTINGS_HELPER_H_
 #define CHROME_BROWSER_BANNERS_APP_BANNER_SETTINGS_HELPER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 22 matching lines @@
 // The desired effect is to have banners appear once a user has demonstrated
 // an ongoing relationship with the app, and not to pester the user too much.
 //
 // For most events only the last event is recorded. The exception are the
 // could show events. For these a list of the events is maintained. At most
 // one event is stored per day, and events outside the window the heuristic
 // uses are discarded. Local times are used to enforce these rules, to ensure
 // what we count as a day matches what the user perceives to be days.
 class AppBannerSettingsHelper {
  public:
+  // TODO(mariakhomenko): Rename events to reflect that they are used in more
+  // contexts now.
   enum AppBannerEvent {
     APP_BANNER_EVENT_COULD_SHOW,
     APP_BANNER_EVENT_DID_SHOW,
     APP_BANNER_EVENT_DID_BLOCK,
     APP_BANNER_EVENT_DID_ADD_TO_HOMESCREEN,
     APP_BANNER_EVENT_NUM_EVENTS,
   };
 
   enum AppBannerRapporMetric {
     WEB,
     NATIVE,
   };
 
+  static const char kInstantAppsKey[];
+
   // BannerEvents record the time that a site was accessed, along with an
   // engagement weight representing the importance of the access.
   struct BannerEvent {
     base::Time time;
     double engagement;
   };
 
   // The content setting basically records a simplified subset of history.
   // For privacy reasons this needs to be cleared. The ClearHistoryForURLs
   // function removes any information from the banner content settings for the
@@ skipping 101 matching lines @@
 
   // Returns true if the app banner trigger condition should use the site
   // engagement score instead of the navigation-based heuristic.
   static bool ShouldUseSiteEngagementScore();
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(AppBannerSettingsHelper);
 };
 
 #endif  // CHROME_BROWSER_BANNERS_APP_BANNER_SETTINGS_HELPER_H_