Instant App Banner logic.

chrome/browser/banners/app_banner_settings_helper.h

Index: chrome/browser/banners/app_banner_settings_helper.h
diff --git a/chrome/browser/banners/app_banner_settings_helper.h b/chrome/browser/banners/app_banner_settings_helper.h
index f19fdeb687abcd343764cccce6510c56f56c194e..bfa4577c6968cfc0a88aad66bb474eecf07706f6 100644
--- a/chrome/browser/banners/app_banner_settings_helper.h
+++ b/chrome/browser/banners/app_banner_settings_helper.h
@@ -40,6 +40,8 @@ class Profile;
 // 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,
@@ -53,6 +55,8 @@ class AppBannerSettingsHelper {
     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 {