Update the web store promo to be clearer and configurable at run-time.

chrome/browser/ui/webui/app_launcher_handler.h

Index: chrome/browser/ui/webui/app_launcher_handler.h
diff --git a/chrome/browser/ui/webui/app_launcher_handler.h b/chrome/browser/ui/webui/app_launcher_handler.h
index f25b555fa7582fdc2a88bb29e5409c7b386a9783..2d0e328d4cdeb0ccfff6a17e8a004c9882dd966a 100644
--- a/chrome/browser/ui/webui/app_launcher_handler.h
+++ b/chrome/browser/ui/webui/app_launcher_handler.h
@@ -55,6 +55,9 @@ class AppLauncherHandler : public WebUIMessageHandler,
   // Populate the given dictionary with all installed app info.
   void FillAppDictionary(DictionaryValue* value);
 
+  // Populate the given dictionary with the web store promo content.
+  void FillPromoDictionary(DictionaryValue* value);
+
   // Callback for the "getApps" message.
   void HandleGetApps(const ListValue* args);
 
@@ -79,6 +82,9 @@ class AppLauncherHandler : public WebUIMessageHandler,
   // Callback for the "setPageIndex" message.
   void HandleSetPageIndex(const ListValue* args);
 
+  // Callback for the "promoSeen" message.
+  void HandlePromoSeen(const ListValue* args);
+
  private:
   // Records a web store launch in the appropriate histograms. |promo_active|
   // specifies if the web store promotion was active.