Method onCloseToLeft

src/services/workbench/editorService.ts:140–140

* Listen to the left tabs close event * @param callback

(callback: (tabItem: IEditorTab, groupId?: UniqueId) => void)

     * @param callback
     */
    onCloseToLeft(callback: (tabItem: IEditorTab, groupId?: UniqueId) => void);
    /**
     * Listen to the right tabs close event
     * @param callback