Improve inheritance support in the CEF API (issue #1623).

- Support single parent inheritance in CEF API classes.
- Support non-virtual inheritance in CEF API classes.
- Support translation of CEF API sub-directories.
- Add test sub-directories for testing-only functionality that will be
  available to unit tests but not exposed via the binary distribution.
- Add unit tests for the translator tool.
- Fix parsing of template parameter types that include commas.

libcef_dll/cpptoc/before_download_callback_cpptoc.h

@@ -28,9 +28,8 @@ class CefBeforeDownloadCallbackCppToC
     : public CefCppToC<CefBeforeDownloadCallbackCppToC,
         CefBeforeDownloadCallback, cef_before_download_callback_t> {
  public:
-  explicit CefBeforeDownloadCallbackCppToC(CefBeforeDownloadCallback* cls);
+  CefBeforeDownloadCallbackCppToC();
 };
 
 #endif  // BUILDING_CEF_SHARED
 #endif  // CEF_LIBCEF_DLL_CPPTOC_BEFORE_DOWNLOAD_CALLBACK_CPPTOC_H_
-