Optimized include/*.h: (recursively) include all headers needed by
this .h file, but only those. Necessary fixes to a lot of .c files,
started optimizing "windows.h" away from some of them. Moved
GetCurrentTask prototype to wine/winbase16.h.
diff --git a/dlls/shell32/classes.c b/dlls/shell32/classes.c
index b65090e..b980b23 100644
--- a/dlls/shell32/classes.c
+++ b/dlls/shell32/classes.c
@@ -8,6 +8,7 @@
#include <string.h>
#include "debug.h"
#include "winerror.h"
+#include "winreg.h"
#include "shlobj.h"
#include "shell32_main.h"
