Application Output: Close pane if the last tab is closed

Change-Id: I782aab3895f27b801c9517cf9ef21f4a474612fd
Task-number: QTCREATORBUG-14395
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/projectexplorer/appoutputpane.cpp

@@ -517,6 +517,10 @@ bool AppOutputPane::closeTab(int tabIndex, CloseTabMode closeTabMode)
     delete m_runControlTabs[index].window;
     m_runControlTabs.removeAt(index);
     updateCloseActions();
+
+    if (m_runControlTabs.isEmpty())
+        hide();
+
     return true;
 }