src/vs/workbench/contrib/webviewPanel/browser/webviewWorkbenchService.ts/WebviewEditorService/shouldPersist
class WebviewEditorService:	public shouldPersist(webview: WebviewInput): boolean {
		// Revived webviews may not have an actively registered reviver but we still want to persist them
		// since a reviver should exist when it is actually needed.
		if (webview instanceof LazilyResolvedWebviewEditorInput) {
			return true;
		}

		return Iterable.some(this._revivers.values(), reviver => canRevive(reviver, webview));
	}