Add metrics for interactions with the Apps Launcher promo dialog.

chrome/browser/ui/webui/ntp/app_launcher_handler.h

Index: chrome/browser/ui/webui/ntp/app_launcher_handler.h
diff --git a/chrome/browser/ui/webui/ntp/app_launcher_handler.h b/chrome/browser/ui/webui/ntp/app_launcher_handler.h
index 986d055b0cc7f35068c6fb3ca19ccd69bcd64755..7a5dc0f7ebd36c287606a32086a960e6e2f5dad3 100644
--- a/chrome/browser/ui/webui/ntp/app_launcher_handler.h
+++ b/chrome/browser/ui/webui/ntp/app_launcher_handler.h
@@ -8,6 +8,7 @@
 #include <set>
 #include <string>
 
+#include "apps/metrics_names.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/pref_change_registrar.h"
 #include "chrome/browser/extensions/extension_uninstall_dialog.h"
@@ -68,31 +69,41 @@ class AppLauncherHandler : public content::WebUIMessageHandler,
   // Populate the given dictionary with the web store promo content.
   void FillPromoDictionary(base::DictionaryValue* value);
 
-  // Callback for the "getApps" message.
+  // Handles the "launchApp" message with unused |args|.
   void HandleGetApps(const base::ListValue* args);
 
-  // Callback for the "launchApp" message.
+  // Handles the "launchApp" message with |args| containing [extension_id,
+  // source] with optional [url, disposition], |disposition| defaulting to
+  // CURRENT_TAB.
   void HandleLaunchApp(const base::ListValue* args);
 
-  // Callback for the "setLaunchType" message.
+  // Handles the "setLaunchType" message with args containing [extension_id,
+  // launch_type].
   void HandleSetLaunchType(const base::ListValue* args);
 
-  // Callback for the "uninstallApp" message.
+  // Handles the "uninstallApp" message with |args| containing [extension_id]
+  // and an optional bool to not confirm the uninstall when true, defaults to
+  // false.
   void HandleUninstallApp(const base::ListValue* args);
 
-  // Callback for the "createAppShortcut" message.
+  // Handles the "createAppShortcut" message with |args| containing
+  // [extension_id].
   void HandleCreateAppShortcut(const base::ListValue* args);
 
-  // Callback for the "reorderApps" message.
+  // Handles the "reorderApps" message with |args| containing [dragged_app_id,
+  // app_order].
   void HandleReorderApps(const base::ListValue* args);
 
-  // Callback for the "setPageIndex" message.
+  // Handles the "setPageIndex" message with |args| containing [extension_id,
+  // page_index].
   void HandleSetPageIndex(const base::ListValue* args);
 
-  // Callback for the "saveAppPageName" message.
+  // Handles "saveAppPageName" message with |args| containing [name,
+  // page_index].
   void HandleSaveAppPageName(const base::ListValue* args);
 
-  // Callback for the "generateAppForLink" message.
+  // Handles "generateAppForLink" message with |args| containing [url, title,
+  // page_index].
   void HandleGenerateAppForLink(const base::ListValue* args);
 
   // Callback for the "recordAppLaunchByURL" message. Takes an escaped URL and a
@@ -100,14 +111,9 @@ class AppLauncherHandler : public content::WebUIMessageHandler,
   // action for UMA.
   void HandleRecordAppLaunchByUrl(const base::ListValue* args);
 
-  // Callback for "stopShowingAppLauncherPromo" message.
+  // Other registered message callbacks with unused |args|.
   void StopShowingAppLauncherPromo(const base::ListValue* args);
-
-  // Callback for "closeNotification" message.
-  void HandleNotificationClose(const base::ListValue* args);
-
-  // Callback for "setNotificationsDisabled" message.
-  void HandleSetNotificationsDisabled(const base::ListValue* args);
+  void OnLearnMore(const base::ListValue* args);
 
   // Register app launcher preferences.
   static void RegisterUserPrefs(user_prefs::PrefRegistrySyncable* registry);
@@ -122,6 +128,10 @@ class AppLauncherHandler : public content::WebUIMessageHandler,
   // Records an app launch from the main view of the app list.
   static void RecordAppListMainLaunch(const extensions::Extension* extension);
 
+  // Records the given |value| in the apps::kAppLauncherPromoHistogram.
+  static void RecordAppLauncherPromoHistogram(
+      apps::AppLauncherPromoHistogramValues value);
+
  private:
   struct AppInstallInfo {
     AppInstallInfo();