Ref pointers don't need a pointer ID and reserving space would render
the code incompatible with other clients. Note that the pointer
marshalling/unmarshalling functions didn't actually read/write pointer
IDs to/from the reserved space in the buffer.

rpcrt4: Fix NdrComplexArrayUnmarshall and NdrComplexStructUnmarshall to reuse memory for embedded pointers.

Certain WM_LBUTTONDOWN & WM_LBUTTONUP events should change focus to the
ComboBox (a child of ComboBoxEx), but instead the focus was set to the
Edit control.

Fixes a bug valgrind found.

    
This essentially reverts 2f69329a.
We really need the visible rect to be set atomically with the rest of
the window position info.

Also avoid dependency on winternl.h.