test: refactor test-domain-from-timer

In this change, the setTimeout needed a second argument, so I set that
value to 1. In addition, I changed the assertion to be a strictEquals
instead of equals.

I changed the var declarations to const in this test.

PR-URL: nodejs#9889
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/test-domain-from-timer.js

@@ -2,17 +2,17 @@
 // Simple tests of most basic domain functionality.
 
 require('../common');
-var assert = require('assert');
+const assert = require('assert');
 
 // timeouts call the callback directly from cc, so need to make sure the
 // domain will be used regardless
 setTimeout(function() {
-  var domain = require('domain');
-  var d = domain.create();
+  const domain = require('domain');
+  const d = domain.create();
   d.run(function() {
     process.nextTick(function() {
       console.trace('in nexttick', process.domain === d);
-      assert.equal(process.domain, d);
+      assert.strictEqual(process.domain, d);
     });
   });
-});
+}, 1);