test: invoke callback with common.mustCall()

* invoke callback with `common.mustCall()` in test-crypto-hash
* order module declarations aphabetically per test-writing-guide

PR-URL: https://github.com/nodejs/node/pull/8597
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

test/parallel/test-crypto-domain.js

@@ -4,8 +4,8 @@ if (!common.hasCrypto)
   common.skip('missing crypto');
 
 const assert = require('assert');
-const domain = require('domain');
 const crypto = require('crypto');
+const domain = require('domain');
 
 function test(fn) {
   const ex = new Error('BAM');

test/parallel/test-crypto-hash.js

@@ -80,11 +80,11 @@ const fileStream = fs.createReadStream(fn);
 fileStream.on('data', function(data) {
   sha1Hash.update(data);
 });
-fileStream.on('close', function() {
+fileStream.on('close', common.mustCall(function() {
   assert.strictEqual(sha1Hash.digest('hex'),
                      '22723e553129a336ad96e10f6aecdf0f45e4149e',
                      'Test SHA1 of sample.png');
-});
+}));
 
 // Issue #2227: unknown digest method should throw an error.
 assert.throws(function() {