DevTools: improve javascript formatter to support "return" properties.

Source/devtools/front_end/script_formatter_worker/JavaScriptFormatter.js

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 23 matching lines @@
  * @param {!FormatterWorker.JavaScriptFormattedContentBuilder} builder
  */
 FormatterWorker.JavaScriptFormatter = function(tokenizer, builder)
 {
     this._tokenizer = tokenizer;
     this._builder = builder;
     this._token = null;
     this._nextToken = this._tokenizer.next();
 }
 
+FormatterWorker.JavaScriptFormatter._identifierRegex = /^[$A-Z_][0-9A-Z_$]*$/i;
+
 FormatterWorker.JavaScriptFormatter.prototype = {
     format: function()
     {
         this._parseSourceElements(FormatterWorker.JavaScriptTokens.EOS);
         this._consume(FormatterWorker.JavaScriptTokens.EOS);
     },
 
     /**
      * @return {number}
      */
@@ skipping 30 matching lines @@
     /**
      * @param {number} token
      */
     _expect: function(token)
     {
         var next = this._next();
         if (next !== token)
             throw "Unexpected token: expected " + token + ", actual " + next;
     },
 
+    _expectGeneralIdentifier: function()
+    {
+        var next = this._next();
+        if (next !== FormatterWorker.JavaScriptTokens.IDENTIFIER && !FormatterWorker.JavaScriptFormatter._identifierRegex.test(this._token.value))
+            throw "Unexpected token: expected javascript identifier, actual " + this._token.value;
+    },
+
     _expectSemicolon: function()
     {
         if (this._peek() === FormatterWorker.JavaScriptTokens.SEMICOLON)
             this._consume(FormatterWorker.JavaScriptTokens.SEMICOLON);
     },
 
     /**
      * @return {boolean}
      */
     _hasLineTerminatorBeforeNext: function()
@@ skipping 411 matching lines @@
                 this._parseExpression();
                 this._expect(FormatterWorker.JavaScriptTokens.RBRACK);
                 break;
 
             case FormatterWorker.JavaScriptTokens.LPAREN:
                 this._parseArguments();
                 break;
 
             case FormatterWorker.JavaScriptTokens.PERIOD:
                 this._consume(FormatterWorker.JavaScriptTokens.PERIOD);
-                this._expect(FormatterWorker.JavaScriptTokens.IDENTIFIER);
+                this._expectGeneralIdentifier();
                 break;
 
             default:
                 return;
             }
         }
     },
 
     _parseNewExpression: function()
     {
@@ skipping 20 matching lines @@
         while (true) {
             switch (this._peek()) {
             case FormatterWorker.JavaScriptTokens.LBRACK:
                 this._consume(FormatterWorker.JavaScriptTokens.LBRACK);
                 this._parseExpression();
                 this._expect(FormatterWorker.JavaScriptTokens.RBRACK);
                 break;
 
             case FormatterWorker.JavaScriptTokens.PERIOD:
                 this._consume(FormatterWorker.JavaScriptTokens.PERIOD);
-                this._expect(FormatterWorker.JavaScriptTokens.IDENTIFIER);
+                this._expectGeneralIdentifier();
                 break;
 
             case FormatterWorker.JavaScriptTokens.LPAREN:
                 this._parseArguments();
                 break;
 
             default:
                 return;
             }
         }
@@ skipping 442 matching lines @@
     {
         var token = FormatterWorker.JavaScriptTokensByType[uglifyToken.type];
         if (typeof token === "number")
             return token;
         token = FormatterWorker.JavaScriptTokensByValue[uglifyToken.value];
         if (typeof token === "number")
             return token;
         throw "Unknown token type " + uglifyToken.type;
     }
 }