[ChromeDriver] Select the main frame if a non-existant child frame is targeted.

chrome/test/chromedriver/stub_chrome.h

Index: chrome/test/chromedriver/stub_chrome.h
diff --git a/chrome/test/chromedriver/stub_chrome.h b/chrome/test/chromedriver/stub_chrome.h
new file mode 100644
index 0000000000000000000000000000000000000000..ed57acac45b95f9848192fb0a70abe73bcde2160
--- /dev/null
+++ b/chrome/test/chromedriver/stub_chrome.h
@@ -0,0 +1,44 @@
+// 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_STUB_CHROME_H_
+#define CHROME_TEST_CHROMEDRIVER_STUB_CHROME_H_
+
+#include <list>
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "chrome/test/chromedriver/chrome.h"
+
+class Status;
+
+class StubChrome : public Chrome {
+ public:
+  StubChrome();
+  virtual ~StubChrome();
+
+  // Overridden from Chrome:
+  virtual Status Load(const std::string& url) OVERRIDE;
+  virtual Status Reload() OVERRIDE;
+  virtual Status EvaluateScript(const std::string& frame,
+                                const std::string& function,
+                                scoped_ptr<base::Value>* result) OVERRIDE;
+  virtual Status CallFunction(const std::string& frame,
+                              const std::string& function,
+                              const base::ListValue& args,
+                              scoped_ptr<base::Value>* result) OVERRIDE;
+  virtual Status GetFrameByFunction(const std::string& frame,
+                                    const std::string& function,
+                                    const base::ListValue& args,
+                                    std::string* out_frame) OVERRIDE;
+  virtual Status DispatchMouseEvents(
+      const std::list<MouseEvent>& events) OVERRIDE;
+  virtual Status DispatchKeyEvents(const std::list<KeyEvent>& events) OVERRIDE;
+  virtual Status Quit() OVERRIDE;
+  virtual Status WaitForPendingNavigations(
+      const std::string& frame_id) OVERRIDE;
+  virtual Status GetMainFrame(std::string* frame_id) OVERRIDE;
+};
+
+#endif  // CHROME_TEST_CHROMEDRIVER_STUB_CHROME_H_