DevTools: add test to verify simple selector behavior.

Source/devtools/front_end/elements/StylesSidebarPane.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * 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 1856 matching lines @@
         }
 
         /**
          * @param {!WebInspector.CSSRule} newRule
          * @this {WebInspector.StylePropertiesSection}
          */
         function successCallback(newRule)
         {
             var doesSelectorAffectSelectedNode = newRule.matchingSelectors.length > 0;
             var styleRule = { section: this, style: newRule.style, selectorText: newRule.selectorText, sourceURL: newRule.resourceURL(), rule: newRule };
-            this.makeNormal(styleRule);
+            this._makeNormal(styleRule);
 
             if (!doesSelectorAffectSelectedNode) {
                 this.noAffect = true;
                 this.element.classList.add("no-affect");
             }
 
             this._updateRuleOrigin();
             this.expand();
             if (this.element.parentElement) // Might have been detached already.
                 this._moveEditorFromSelector(moveDirection);
@@ skipping 29 matching lines @@
         delete this._parentPane._userOperation;
         if (!this.isBlank) {
             WebInspector.StylePropertiesSection.prototype.editingSelectorCancelled.call(this);
             return;
         }
 
         this._editingSelectorEnded();
         this._parentPane.removeSection(this);
     },
 
-    makeNormal: function(styleRule)
+    _makeNormal: function(styleRule)
     {
         this.element.classList.remove("blank-section");
         this.styleRule = styleRule;
         this.rule = styleRule.rule;
 
         // FIXME: replace this instance by a normal WebInspector.StylePropertiesSection.
         this._normal = true;
     },
 
     __proto__: WebInspector.StylePropertiesSection.prototype
@@ skipping 1373 matching lines @@
         if (userEnteredText && (userEnteredText === userEnteredText.toUpperCase())) {
             for (var i = 0; i < results.length; ++i)
                 results[i] = results[i].toUpperCase();
         }
         var selectedIndex = this._cssCompletions.mostUsedOf(results);
         completionsReadyCallback(results, selectedIndex);
     },
 
     __proto__: WebInspector.TextPrompt.prototype
 }