test: invoke callback with common.mustCall()

test: invoke callback with common.mustCall() · nodejs/node@a284ee6

Original file line number	Diff line number	Diff line change
`@@ -80,11 +80,11 @@ const fileStream = fs.createReadStream(fn);`
`80`	`80`	`fileStream.on('data', function(data) {`
`81`	`81`	`sha1Hash.update(data);`
`82`	`82`	`});`
`83`		`-fileStream.on('close', function() {`
	`83`	`+fileStream.on('close', common.mustCall(function() {`
`84`	`84`	`assert.strictEqual(sha1Hash.digest('hex'),`
`85`	`85`	`'22723e553129a336ad96e10f6aecdf0f45e4149e',`
`86`	`86`	`'Test SHA1 of sample.png');`
`87`		`-});`
	`87`	`+}));`
`88`	`88`
`89`	`89`	`// Issue #2227: unknown digest method should throw an error.`
`90`	`90`	`assert.throws(function() {`