DevTools: Polish uiSourceCode context menu on sources panel.

Source/devtools/front_end/sources/SourcesPanel.js

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 872 matching lines @@
      * @param {?Event} event
      * @param {!WebInspector.ContextMenu} contextMenu
      * @param {!Object} target
      */
     _appendUISourceCodeItems: function(event, contextMenu, target)
     {
         if (!(target instanceof WebInspector.UISourceCode))
             return;
 
         var uiSourceCode = /** @type {!WebInspector.UISourceCode} */ (target);
-        contextMenu.appendItem(WebInspector.UIString(WebInspector.useLowerCaseMenuTitles() ? "Local modifications\u2026" : "Local Modifications\u2026"), this._showLocalHistory.bind(this, uiSourceCode));
+        var project = uiSourceCode.project();
+        if (project.type() !== WebInspector.projectTypes.FileSystem)
+            contextMenu.appendItem(WebInspector.UIString(WebInspector.useLowerCaseMenuTitles() ? "Local modifications\u2026" : "Local Modifications\u2026"), this._showLocalHistory.bind(this, uiSourceCode));
         this._appendUISourceCodeMappingItems(contextMenu, uiSourceCode);
 
         if (!event.target.isSelfOrDescendant(this.editorView.sidebarElement())) {
             contextMenu.appendSeparator();
             contextMenu.appendItem(WebInspector.UIString(WebInspector.useLowerCaseMenuTitles() ? "Reveal in navigator" : "Reveal in Navigator"), this._handleContextMenuReveal.bind(this, uiSourceCode));
         }
     },
 
     /**
      * @param {!WebInspector.UISourceCode} uiSourceCode
@@ skipping 505 matching lines @@
 WebInspector.SourcesPanel.TogglePauseActionDelegate.prototype = {
     /**
      * @return {boolean}
      */
     handleAction: function()
     {
         /** @type {!WebInspector.SourcesPanel} */ (WebInspector.inspectorView.showPanel("sources")).togglePause();
         return true;
     }
 }