Take notification API out of experimental.

chrome/browser/extensions/event_names.cc

Index: chrome/browser/extensions/event_names.cc
diff --git a/chrome/browser/extensions/event_names.cc b/chrome/browser/extensions/event_names.cc
index 3db4f58a42568aba0bf3d3f305733444a15ebe9f..070238ec812560c171bde8ec19fa2fff3ef4e06c 100644
--- a/chrome/browser/extensions/event_names.cc
+++ b/chrome/browser/extensions/event_names.cc
@@ -89,12 +89,11 @@ const char kOnDetachEventName[] = "mediaGalleriesPrivate.onDeviceDetached";
 const char kOnGalleryChangedEventName[] =
     "mediaGalleriesPrivate.onGalleryChanged";
 
-const char kOnNotificationDisplayed[] = "experimental.notification.onDisplayed";
-const char kOnNotificationError[] = "experimental.notification.onError";
-const char kOnNotificationClosed[] = "experimental.notification.onClosed";
-const char kOnNotificationClicked[] = "experimental.notification.onClicked";
-const char kOnNotificationButtonClicked[] =
-    "experimental.notification.onButtonClicked";
+const char kOnNotificationDisplayed[] = "notifications.onDisplayed";
+const char kOnNotificationError[] = "notifications.onError";
+const char kOnNotificationClosed[] = "notifications.onClosed";
+const char kOnNotificationClicked[] = "notifications.onClicked";
+const char kOnNotificationButtonClicked[] = "notifications.onButtonClicked";
 
 const char kOnNetworksChanged[] = "networkingPrivate.onNetworksChanged";
 const char kOnNetworkListChanged[] = "networkingPrivate.onNetworkListChanged";