Debugger: Apply on Save only when Engine client is connected

Creation of the Text previews are done only when the engine client
is connected and they are deleted once the engine client changes
from the connected state.

Change-Id: I325d0d1a281b9e8fab4ddf9ff8ea4f5e60d4ac2a
Reviewed-by: Kai Koehne <kai.koehne@nokia.com>

src/plugins/debugger/qml/qmlinspectoradapter.h

@@ -114,6 +114,7 @@ private:
     void selectObject(
             const QmlDebug::ObjectReference &objectReference,
             SelectionTarget target);
+    void deletePreviews();
 
 
     QmlAdapter *m_debugAdapter;
@@ -142,6 +143,8 @@ private:
     Core::Context m_inspectorToolsContext;
     QAction *m_selectAction;
     QAction *m_zoomAction;
+
+    bool m_engineClientConnected;
 };
 
 } // namespace Internal