Rewrite text field context menu tests using accessiblity framework....

chrome_frame/test/chrome_frame_test_utils.h

Index: chrome_frame/test/chrome_frame_test_utils.h
===================================================================
--- chrome_frame/test/chrome_frame_test_utils.h	(revision 65066)
+++ chrome_frame/test/chrome_frame_test_utils.h	(working copy)
@@ -148,6 +148,13 @@
 // Adds the CF meta tag to the html page. Returns true if successful.
 bool AddCFMetaTag(std::string* html_data);
 
+// Get text data from the clipboard.
+std::wstring GetClipboardText();
+
+// Puts the given text data on the clipboard. All previous items on the
+// clipboard are removed.
+void SetClipboardText(const std::wstring& text);
+
 // A convenience class to close all open IE windows at the end
 // of a scope.  It's more convenient to do it this way than to
 // explicitly call chrome_frame_test::CloseAllIEWindows at the