src/vs/platform/userDataSync/common/keybindingsSync.ts/getKeybindingsContentFromSyncContent
export function getKeybindingsContentFromSyncContent(syncContent: string, platformSpecific: boolean): string | null {
	const parsed = <ISyncContent>JSON.parse(syncContent);
	if (!platformSpecific) {
		return isUndefined(parsed.all) ? null : parsed.all;
	}
	switch (OS) {
		case OperatingSystem.Macintosh:
			return isUndefined(parsed.mac) ? null : parsed.mac;
		case OperatingSystem.Linux:
			return isUndefined(parsed.linux) ? null : parsed.linux;
		case OperatingSystem.Windows:
			return isUndefined(parsed.windows) ? null : parsed.windows;
	}
}