CHttpRequest fixed content end

@cebe i've fixed that issue - https://github.com/yiisoft/yii/issues/2479, but also need your help here, because i can not simply move tests from Yii2 for this component to Yii1 because of i need to define my custom ```header``` function as in Yii2 ```ResponseTest```, but here in Yii1 i cant do this, i always get error ```cannot redeclare function```, how to avoid this pitfall?