clear_presets_change

function ClearPreset(event)
{
    // event can either be a triggered event, or the id string of the element that is changing
    var id = event;  // default if event is id string
    var element = $(this); // default if event is triggered event
    if ("object" == typeof(event)) {id = element.attr('id');} // event is triggered event -- get real id string
    if ("string" == typeof(event)) {element = $('#' + event);} // event is id string -- get real element
    
    var exceptions = ['gpu_select','audio_selector_select'];
    
    var element_excepted = false;
    for (var i=0; i < exceptions.length; i++) {
      if (element.hasClass(exceptions[i])) {
        element_excepted = true;
      }
    };
    
    if (should_update_preset && id.substring(0, 3) != 'vp_' && !element_excepted) {
        var preset = id.replace(/(\w+_(media|stream_assemblies)_attributes_\d+).*/, "$1_preset_id");
        $("#" + preset + " option:eq(0)").prop('selected', true);
        
        if(typeof(event) === event) {
            var stream_assembly_name = $(this).parents('.stream').data('name');  
            if( ElementalUI.get_controller() != 'presets') {
                var stream_assembly_object = GlobalStreamAssemblyManager.find(stream_assembly_name);
                stream_assembly_object.preset = null;
            }  
            $(document).trigger('stream_assembly_preset_change',[stream_assembly_name]);
        }
        $(document).trigger('stream_assembly_change');
    }
}