fix missing replacement

Author: calvinmetcalf

build/test-replacements.js

@@ -147,7 +147,12 @@ module.exports['common.js'] = [
     /^var util = require\('util'\);/m
   ,   '\n/*<replacement>*/\nvar util = require(\'core-util-is\');\n'
     + 'util.inherits = require(\'inherits\');\n/*</replacement>*/\n'
-  ]
+  ],
+  [
+  /^const util = require\('util'\);/m
+,   '\n/*<replacement>*/\nvar util = require(\'core-util-is\');\n'
+  + 'util.inherits = require(\'inherits\');\n/*</replacement>*/\n'
+]
 ]
 
 // this test has some trouble with the nextTick depth when run

test/common.js

@@ -30,7 +30,12 @@ var assert = require('assert');
 var os = require('os');
 var child_process = require('child_process');
 var stream = require('../');
-var util = require('util');
+
+/*<replacement>*/
+var util = require('core-util-is');
+util.inherits = require('inherits');
+/*</replacement>*/
+
 
 var testRoot = path.resolve(process.env.NODE_TEST_DIR || 
 path.dirname(__filename));