cleanup: remove unused code in requireDir()

No changes in functionality.

index.js

@@ -232,20 +232,13 @@ function forEachKeyedObject(obj, fn) {
   });
 }
 
-function requireDir(dir, basenames) {
+function requireDir(dir) {
   assert(dir, 'cannot require directory contents without directory name');
 
   var requires = {};
 
-  if (arguments.length === 2) {
-    // if basenames argument is passed, explicitly include those files
-    basenames.forEach(function (basename) {
-      var filepath = path.resolve(path.join(dir, basename));
-      requires[basename] = tryRequire(filepath);
-    });
-  } else if (arguments.length === 1) {
-    // if basenames arguments isn't passed, require all javascript
-    // files (except for those prefixed with _) and all directories
+  // require all javascript files (except for those prefixed with _)
+  // and all directories
 
   var files = tryReadDir(dir);
 
@@ -265,22 +258,24 @@ function requireDir(dir, basenames) {
 
   files.forEach(function(filename) {
     // ignore index.js and files prefixed with underscore
-      if ((filename === 'index.js') || (filename[0] === '_')) { return; }
+    if ((filename === 'index.js') || (filename[0] === '_')) {
+      return;
+    }
 
     var filepath = path.resolve(path.join(dir, filename));
     var ext = path.extname(filename);
     var stats = fs.statSync(filepath);
 
     // only require files supported by require.extensions (.txt .md etc.)
-      if (stats.isFile() && !(ext in require.extensions)) { return; }
+    if (stats.isFile() && !(ext in require.extensions)) {
+      return;
+    }
 
     var basename = path.basename(filename, ext);
 
     requires[basename] = tryRequire(filepath);
   });
 
-  }
-
   return requires;
 }