Sync code with fbjs to fix a bug

warning.js

@@ -14,47 +14,39 @@
  * same logic and follow the same code paths.
  */
 
-var __DEV__ = process.env.NODE_ENV !== 'production';
-
 var warning = function() {};
 
-if (__DEV__) {
-  var printWarning = function printWarning(format, args) {
-    var len = arguments.length;
-    args = new Array(len > 2 ? len - 2 : 0);
-    for (var key = 2; key < len; key++) {
-      args[key - 2] = arguments[key];
+if (process.env.NODE_ENV !== 'production') {
+  var printWarning = function printWarning(format) {
+    for (var _len = arguments.length, args = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
+      args[_key - 1] = arguments[_key];
     }
+
     var argIndex = 0;
-    var message = 'Warning: ' +
-      format.replace(/%s/g, function() {
-        return args[argIndex++];
-      });
+    var message = 'Warning: ' + format.replace(/%s/g, function () {
+      return args[argIndex++];
+    });
     if (typeof console !== 'undefined') {
       console.error(message);
     }
     try {
-      // --- Welcome to debugging React ---
       // This error was thrown as a convenience so that you can use this stack
       // to find the callsite that caused this warning to fire.
       throw new Error(message);
     } catch (x) {}
-  }
+  };
 
-  warning = function(condition, format, args) {
-    var len = arguments.length;
-    args = new Array(len > 2 ? len - 2 : 0);
-    for (var key = 2; key < len; key++) {
-      args[key - 2] = arguments[key];
-    }
+  warning = function warning(condition, format) {
     if (format === undefined) {
-      throw new Error(
-          '`warning(condition, format, ...args)` requires a warning ' +
-          'message argument'
-      );
+      throw new Error('`warning(condition, format, ...args)` requires a warning ' + 'message argument');
     }
+
     if (!condition) {
-      printWarning.apply(null, [format].concat(args));
+      for (var _len2 = arguments.length, args = Array(_len2 > 2 ? _len2 - 2 : 0), _key2 = 2; _key2 < _len2; _key2++) {
+        args[_key2 - 2] = arguments[_key2];
+      }
+
+      printWarning.apply(undefined, [format].concat(args));
     }
   };
 }