Add a UI test for "Encoding" menu

chrome/test/ui/ui_test.h

Index: chrome/test/ui/ui_test.h
===================================================================
--- chrome/test/ui/ui_test.h	(revision 10924)
+++ chrome/test/ui/ui_test.h	(working copy)
@@ -331,6 +331,12 @@
   // error.
   DictionaryValue* GetDefaultProfilePreferences();
 
+  // Generate the file path for testing a particular test.
+  // The file for the tests is all located in
+  // test_root_directory\test_directory\<testcase>
+  static std::wstring GetTestFilePath(const std::wstring& test_directory,
+                                      const std::wstring &test_case);
+
   // Generate the URL for testing a particular test.
   // HTML for the tests is all located in
   // test_root_directory\test_directory\<testcase>
@@ -344,6 +350,15 @@
                      const std::string& test_complete_cookie,
                      const std::string& expected_cookie_value,
                      const int wait_time);
+
+  // Waits for a generated file ready, then check it with the original file
+  // to see whether they are equal or not. Also this function will delete the
+  // generated file if the input parameter |delete_generate_file| is true.
+  void WaitForGeneratedFileAndCheck(const std::wstring& generated_file,
+                                    const std::wstring& original_file,
+                                    bool need_equal,
+                                    bool delete_generate_file);
+
  private:
   // Check that no processes related to Chrome exist, displaying
   // the given message if any do.