Tests errors when finding DOM nodes by computed styles.
{
    error : {
        code : -32000
        message : DOM agent hasn't been enabled
    }
    id : <number>
    sessionId : <string>
}
{
    error : {
        code : -32000
        message : Could not find node with given id
    }
    id : <number>
    sessionId : <string>
}
{
    error : {
        code : -32602
        message : Invalid CSS property name
    }
    id : <number>
    sessionId : <string>
}