[cros] Change how we track momemt to emit login-prompt-visible signal.

chrome/common/chrome_notification_types.h

Index: chrome/common/chrome_notification_types.h
diff --git a/chrome/common/chrome_notification_types.h b/chrome/common/chrome_notification_types.h
index cf151dac83743f818aa5940a9879d13d99aa2726..ef28626d2e11f4eae680695e6b93b9480e64ff62 100644
--- a/chrome/common/chrome_notification_types.h
+++ b/chrome/common/chrome_notification_types.h
@@ -891,6 +891,14 @@ enum NotificationType {
   // Sent when the user images on the WebUI login screen have all been loaded.
   NOTIFICATION_LOGIN_USER_IMAGES_LOADED,
 
+  // Sent when the login WebUI is considered to be fully visible.
+  // That momemnt is tracked as the first paint event after one of the:
+  // 1. NOTIFICATION_LOGIN_USER_IMAGES_LOADED

[Daniel Erat, 2012/06/02 14:20:59]

Can you delete some of these, too?  I only added the _USER_IMAGES_LOADED
notification so we could tell when the WebUI is visible -- if it's not needed in
order to send the _WEBUI_VISIBLE notification, I think that it can be removed.

[Nikita (slow), 2012/06/04 09:03:21]

I think it makes sense to leave this _USER_IMAGES_LOADED notification.

They are used by automation proxy.

Even though they may be seen as duplicating _WEBUI_VISIBLE but in fact
_WEBUI_VISIBLE just says that one of the parts of WebUI login is ready/visible,
those 4 others say specifically which one is ready to be used and was shown.

Current usage in automation proxy is when on of the
_USER_IMAGES_LOADED, _LOGIN_WEBUI_READY, _WIZARD_FIRST_SCREEN_SHOWN is firedm
report event "WebUI ready". But we may as well improve on that and require
specific notification.

For instance when we're booting into image w/o users we're waiting for
_LOGIN_WEBUI_READY, not for _USER_IMAGES_LOADED.

+  // 2. NOTIFICATION_LOGIN_WEBUI_READY
+  // 3. NOTIFICATION_LOGIN_NETWORK_ERROR_SHOWN
+  // 4. NOTIFICATION_WIZARD_FIRST_SCREEN_SHOWN
+  NOTIFICATION_LOGIN_WEBUI_VISIBLE,
+
   // Sent when proxy dialog is closed.
   NOTIFICATION_LOGIN_PROXY_CHANGED,