[PATCH 0/2] MR308: Add "wine/str.h", use "wine/heap.h" and it in winemenubuilder

[Davide Beatrici (@davidebeatrici)]

```c
include/wine/str.h:32:29: warning: the address of ‘buffer’ will always evaluate as ‘true’ [-Waddress]
   32 | #define utf16len(str)  (str ? wcslen(str) : 0)
      |                             ^
programs/winemenubuilder/winemenubuilder.c:1474:15: note: in expansion of macro ‘utf16len’
 1474 |         len = utf16len(buffer);
      |               ^~~~~~~~
```

I should probably transform the macros that validate the argument into functions.

What's the best way to test `winemenubuilder` and make sure I didn't break anything?

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/308#note_2604