Tracks a workbook's name (getName()) as React state, updating on IWorkbook.IListeners.onNameChange.
Parameters
workbook: IWorkbook|null
The workbook to track, or null.
Returns string|null
The current workbook name, or null when there is no workbook / no name.
Remarks
A small model observer so the title shown by chrome (a tab title, the Studio title bar, etc.)
follows the workbook's name reactively rather than reading it once.
Tracks a workbook's name (
getName()) as React state, updating on IWorkbook.IListeners.onNameChange.