src/vs/platform/files/common/ipcFileSystemProvider.ts/IPCFileSystemProvider/watch
class IPCFileSystemProvider:	watch(resource: URI, opts: IWatchOptions): IDisposable {
		const req = Math.random();
		this.channel.call('watch', [this.session, req, resource, opts]);

		return toDisposable(() => this.channel.call('unwatch', [this.session, req]));
	}