switchSelectionFromOldToNewStep(selectedStep, stepToSelect, stepToSelectIndex, changeWithClick) {
      if (selectedStep && stepToSelect) {
        // keep the selection if next step is disabled
        if (!stepToSelect.disabled) {
          selectedStep.selected = false;
          stepToSelect.selected = true;
        }
        this.fireEvent("step-change", {
          step: stepToSelect,
          previousStep: selectedStep,
          changeWithClick
        });
        this.selectedStepIndex = stepToSelectIndex;
      }
    }
Switches the selection from the old step to the newly selected step.

@param {WizardStep} selectedStep the old step
@param {WizardStep} stepToSelect the step to be selected
@param {Integer} stepToSelectIndex the index of the newly selected step
@param {boolean} changeWithClick the selection changed due to user click in the step navigation
@private