Introduce new API to test mixed state of checkboxes.

content/shell/renderer/test_runner/web_ax_object_proxy.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_SHELL_RENDERER_TEST_RUNNER_WEB_AX_OBJECT_PROXY_H_
 #define CONTENT_SHELL_RENDERER_TEST_RUNNER_WEB_AX_OBJECT_PROXY_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 77 matching lines @@
   bool IsCollapsed();
   bool HasPopup();
   bool IsValid();
   bool IsReadOnly();
   std::string Orientation();
   int ClickPointX();
   int ClickPointY();
   int32_t RowCount();
   int32_t ColumnCount();
   bool IsClickable();
+  bool IsButtonStateMixed();
 
   // Bound methods.
   std::string AllAttributes();
   std::string AttributesOfChildren();
   int LineForIndex(int index);
   std::string BoundsForRange(int start, int end);
   v8::Handle<v8::Object> ChildAtIndex(int index);
   v8::Handle<v8::Object> ElementAtPoint(int x, int y);
   v8::Handle<v8::Object> TableHeader();
   std::string RowIndexRange();
@@ skipping 50 matching lines @@
   v8::Handle<v8::Object> CreateRoot(const blink::WebAXObject&);
 
  private:
   typedef v8::PersistentValueVector<v8::Object> ElementList;
   ElementList elements_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_SHELL_RENDERER_TEST_RUNNER_WEB_AX_OBJECT_PROXY_H_