src/vs/workbench/contrib/search/browser/replaceService.ts/ReplacePreviewModel/update
class ReplacePreviewModel:	private update(sourceModel: ITextModel, replacePreviewModel: ITextModel, fileMatch: FileMatch, override: boolean = false): void {
		if (!sourceModel.isDisposed() && !replacePreviewModel.isDisposed()) {
			this.replaceService.updateReplacePreview(fileMatch, override);
		}
	}