[chromedriver] Support clicking an element in sub frames.

chrome/test/chromedriver/basic_types.h

 // Copyright (c) 2013 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 CHROME_TEST_CHROMEDRIVER_BASIC_TYPES_H_
 #define CHROME_TEST_CHROMEDRIVER_BASIC_TYPES_H_
 
 struct WebPoint {
   WebPoint();
   WebPoint(int x, int y);
   ~WebPoint();
 
-  void offset(int x_, int y_);
+  void Offset(int x_, int y_);
 
   int x;
   int y;
 };
 
 struct WebSize {
   WebSize();
   WebSize(int width, int height);
   ~WebSize();
 
   int width;
   int height;
 };
 
 struct WebRect {
   WebRect();
   WebRect(int x, int y, int width, int height);
   WebRect(const WebPoint& origin, const WebSize& size);
   ~WebRect();
 
-  int x();
-  int y();
-  int width();
-  int height();
+  int X() const;
+  int Y() const;
+  int Width() const;
+  int Height() const;
 
   WebPoint origin;
   WebSize size;
 };
 
 #endif  // CHROME_TEST_CHROMEDRIVER_BASIC_TYPES_H_