Stops the editor from updating the view layout and rendering the content if any change is applied. This is useful to increase the control's speed efficiency.
SheetEditor.prototype.beginUpdate = function()
Calls to beginUpdate and endUpdate are accumulative. Each call to beginUpdate must be matched with a corresponding call to endUpdate or else updates to the editor might not be applied.
When the final endUpdate is called and updating is resumed, the editor will render the new content.