Log Message:
Changes 2.8.4:
* IconTheme: Avoid crash in get_search_path().
* Some code size reduction by using more static functions instead of
  anonymous namespaces, and by avoiding some code duplication.
* Windows Build:
  - MSVC++ build: Use the new /vd2 compiler option to get the new unbroken
  dynamic_cast<> with MSVC++. There are now no known problems with
  the MSVC++ build.
  - mingw32 and cygwin builds: Correct some API export/import problems.