fix : AvailableAccountModel uses

- after last meeting it was decided to not show disabled accounts
in combobox_account_selector. We are now using AvailableAccountModel.

- this patch fix several bugs :
  * display the right information on ringwelcomeview.
  * get_active_ring_account() returns the right selected account.
  * bind the selection from combobox_account_selector to
    AvailableAccountModel.
  * use currentChanged signal from selectionModel() to refresh
    treeview_conversations.
  * select the good account in AvailableAccountModel during an
    incoming call.

Change-Id: I652da29da57ab5d6d4f1abe26dd3c2cbf807396c
diff --git a/src/utils/accounts.cpp b/src/utils/accounts.cpp
index bbc182b..b9aa20e 100644
--- a/src/utils/accounts.cpp
+++ b/src/utils/accounts.cpp
@@ -20,6 +20,7 @@
 #include "accounts.h"
 
 #include <accountmodel.h>
+#include <availableaccountmodel.h>
 
 // LRC
 #include <QItemSelectionModel>
@@ -58,6 +59,8 @@
 Account*
 get_active_ring_account()
 {
-    auto account = AccountModel::instance().userChosenAccount();
+    const auto idx = AvailableAccountModel::instance().selectionModel()->currentIndex();
+    auto account = idx.data(static_cast<int>(Account::Role::Object)).value<Account*>();
+
     return (account && account->protocol() == Account::Protocol::RING) ? account : nullptr;
 }