Shared components used by Firefox and other Mozilla software, including handling of Web content; Gecko, HTML, CSS, layout, DOM, scripts, images, networking, etc. Issues with web page layout probably go here, while Firefox user interface issues belong in the Firefox product. (More info)
This is the basis of our component technology; this covers the mozilla/xpcom source directory and includes the "repository". Unlikely a tester would be able to tell there was an XPCOM problem specifically.
shell32.dll is already linked, so shell32.dll is loaded with xul.dll. So we should use GetModuleHandleW instread. This doesn't need to call FreeLibrary.
Also, nsLocalFileWin is for Windows only, it is no reason to use PR_LoadLibrary.