Fixed suggesting adding more users into multi-profile session when we don't have more

ash/system/user/user_view.cc

Index: ash/system/user/user_view.cc
diff --git a/ash/system/user/user_view.cc b/ash/system/user/user_view.cc
index 52f128da1a52fd41b6430984cfed08dbb0682306..04d758b4f4026a06d5813f244343e566c6466336 100644
--- a/ash/system/user/user_view.cc
+++ b/ash/system/user/user_view.cc
@@ -499,9 +499,13 @@ void UserView::ToggleAddUserMenuOption() {
 
   bool multi_profile_allowed =
       delegate->IsMultiProfileAllowedByPrimaryUserPolicy();
-  add_user_disabled_ = (delegate->NumberOfLoggedInUsers() >=
-                        delegate->GetMaximumNumberOfLoggedInUsers()) ||
-                       !multi_profile_allowed;
+  int admitted_users_to_be_added =
+      delegate->GetNumberOfUsersAdmittedForMultiProfile();
+  DCHECK(admitted_users_to_be_added >= 0);
+  add_user_disabled_ = !multi_profile_allowed ||

[James Cook, 2014/09/22 19:52:23]

Please change this to add_user_enabled_ and invert the initialization and all
the other conditionals. I know you didn't add this member, but I strongly prefer
positive-sense booleans.

[Roman Sorokin (ftl), 2014/09/23 15:42:37]

Done.

+                       admitted_users_to_be_added == 0 ||
+                       (delegate->NumberOfLoggedInUsers() >=
+                        delegate->GetMaximumNumberOfLoggedInUsers());

[James Cook, 2014/09/22 19:52:23]

Given that all the data to decide whether or not a user should be added lives in
the delegate, can you replace GetNumberOfUsersAdmittedForMultiProfile() with
something like bool CanAddUserToMultiProfile(int* error_message_id)?

The decision whether adding is allowed or not is more of a model/controller
decision than a UI view decision.

Moving the logic will also make it easier for you to add a test, as there are
existing tests of SessionStateDelegate but none for this class.

[Roman Sorokin (ftl), 2014/09/23 15:42:37]

Done.

 
   ButtonFromView* button = new ButtonFromView(
       add_user_view,
@@ -519,6 +523,8 @@ void UserView::ToggleAddUserMenuOption() {
     int message_id;
     if (!multi_profile_allowed)
       message_id = IDS_ASH_STATUS_TRAY_MESSAGE_NOT_ALLOWED_PRIMARY_USER;
+    else if (admitted_users_to_be_added == 0)
+      message_id = IDS_ASH_STATUS_TRAY_MESSAGE_OUT_OF_USERS;
     else
       message_id = IDS_ASH_STATUS_TRAY_MESSAGE_CANNOT_ADD_USER;