src/vs/workbench/api/browser/mainThreadEditors.ts/MainThreadTextEditors/_getTextEditorPositionData
class MainThreadTextEditors:	private _getTextEditorPositionData(): ITextEditorPositionData {
		const result: ITextEditorPositionData = Object.create(null);
		for (let editorPane of this._editorService.visibleEditorPanes) {
			const id = this._editorLocator.findTextEditorIdFor(editorPane);
			if (id) {
				result[id] = editorGroupToColumn(this._editorGroupService, editorPane.group);
			}
		}
		return result;
	}