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Source/core/inspector/InjectedScriptSource.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2013 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 990 matching lines @@
         if (subtype === "array") {
             if (typeof obj.length === "number")
                 className += "[" + obj.length + "]";
             return className;
         }
 
         // NodeList in JSC is a function, check for array prior to this.
         if (typeof obj === "function")
             return toString(obj);
 
+        if (typeof obj === "symbol") {
+            try {
+                return Symbol.prototype.toString.call(obj) || "Symbol";
+            } catch (e) {
+                return "Symbol";
+            }
+        }
+
         if (className === "Object") {
             // In Chromium DOM wrapper prototypes will have Object as their constructor name,
             // get the real DOM wrapper name from the constructor property.
             var constructorName = obj.constructor && obj.constructor.name;
             if (constructorName)
                 return constructorName;
         }
         return className;
     }
 }
@@ skipping 600 matching lines @@
      */
     _logEvent: function(event)
     {
         inspectedWindow.console.log(event.type, event);
     }
 }
 
 injectedScript._commandLineAPIImpl = new CommandLineAPIImpl();
 return injectedScript;
 })