src/vs/workbench/services/extensions/node/extensionPoints.ts/ExtensionManifestNLSReplacer/resolveOriginalMessageBundle
class ExtensionManifestNLSReplacer:	private static resolveOriginalMessageBundle(originalMessageBundle: string | null, errors: json.ParseError[]) {
		return new Promise<{ [key: string]: string; } | null>((c, e) => {
			if (originalMessageBundle) {
				pfs.Promises.readFile(originalMessageBundle).then(originalBundleContent => {
					c(json.parse(originalBundleContent.toString(), errors));
				}, (err) => {
					c(null);
				});
			} else {
				c(null);
			}
		});
	}