widl: Call Pointer function for freeing non-conformant strings and for all phases for returned non-conformant strings, as is done for conformant strings.

Also call Pointer functions for any string that isn't a reference pointer.

Document how much of hack duplicating a type in order to change its
pointer type is.

It's slightly quicker than calling pointer phase functions and does
the same job.

The generated code should use NdrSimpleType{Marshall,Unmarshall} instead
of direct buffer access, since the memory size isn't always equal to
the size on the wire and extra checks.

user32/tests: Add a couple of optional message, mark as todo a test that now fails consistently on Wine.

The tests were overly restrictive.  The functions are supposed to
return values less than 0, 0, or greater than 0, whereas the tests
restricted the return values to -1, 0, or 1.  Using less than
0/greater than 0 comparisons rather than == -1 or == 1 should fix a
few failing tests, and match the API descriptions better.

gdiplus: In GdipDrawString do not NULL terminate the buffer. It is unneeded and overruns the buffer.