src/vs/workbench/api/common/extHostWorkspace.ts/ExtHostWorkspace/trySetWorkspaceFolders
class ExtHostWorkspace:	private trySetWorkspaceFolders(folders: vscode.WorkspaceFolder[]): void {

		// Update directly here. The workspace is unconfirmed as long as we did not get an
		// acknowledgement from the main side (via $acceptWorkspaceData)
		if (this._actualWorkspace) {
			this._unconfirmedWorkspace = ExtHostWorkspaceImpl.toExtHostWorkspace({
				id: this._actualWorkspace.id,
				name: this._actualWorkspace.name,
				configuration: this._actualWorkspace.configuration,
				folders,
				isUntitled: this._actualWorkspace.isUntitled
			} as IWorkspaceData, this._actualWorkspace, undefined, this._extHostFileSystemInfo).workspace || undefined;
		}
	}