DevTools: [Persistence] guard against multiple UISourceCodes with similar URL

third_party/WebKit/Source/devtools/front_end/persistence/DefaultMapping.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 /**
  * @unrestricted
  */
 Persistence.DefaultMapping = class {
   /**
    * @param {!Workspace.Workspace} workspace
    * @param {!Workspace.FileSystemMapping} fileSystemMapping
@@ skipping 74 matching lines @@
   }
 
   /**
    * @param {!Workspace.UISourceCode} uiSourceCode
    */
   _bind(uiSourceCode) {
     console.assert(!uiSourceCode[Persistence.DefaultMapping._binding], 'Cannot bind already bound UISourceCode!');
     var binding = this._createBinding(uiSourceCode);
     if (!binding)
       return;
+    // TODO(lushnikov): remove this check once there's a single uiSourceCode per url. @see crbug.com/670180
+    if (binding.network[Persistence.DefaultMapping._binding] || binding.fileSystem[Persistence.DefaultMapping._binding])
+      return;
+
     this._bindings.add(binding);
     binding.network[Persistence.DefaultMapping._binding] = binding;
     binding.fileSystem[Persistence.DefaultMapping._binding] = binding;
 
     binding.fileSystem.addEventListener(
         Workspace.UISourceCode.Events.TitleChanged, this._onFileSystemUISourceCodeRenamed, this);
 
     this._onBindingCreated.call(null, binding);
   }
 
@@ skipping 23 matching lines @@
     this._unbind(binding.network);
     this._bind(binding.network);
   }
 
   dispose() {
     Common.EventTarget.removeEventListeners(this._eventListeners);
   }
 };
 
 Persistence.DefaultMapping._binding = Symbol('DefaultMapping.Binding');