_reflectBackOn() {
      return !this._isHandlingUserInput;
    }
Every time .formattedValue is attempted to sync to the view value (on change/blur and on
modelValue change), this condition is checked. When enhancing it, it's recommended to
call via `return this._myExtraCondition && super._reflectBackOn()`
@overridable
@return {boolean}
@protected