fixed crash when renderable component without model file is selected
fixed crash when renderable component without model file is selected

dreamsxin/LuxEngine,JakubLukas/LumixEngine,zhouxh1023/LumixEngine,gamedevforks/LumixEngine,dreamsxin/LuxEngine,gamedevforks/LumixEngine,galek/LumixEngine,galek/LumixEngine,JakubLukas/LumixEngine,JakubLukas/LumixEngine,zhouxh1023/LumixEngine