The rc.exe that comes with the Windows 11 SDK does not allow one to include
winuser.h directly in the .rc scripts, so make sure that we do not try to
generate the final gtk.rc with it, but instead include windows.h with
WIN32_LEAN_AND_MEAN defined.
This will ensure that the version info is easily visible from the
GDK/GTK+ DLLs, and ensure that the print dialogs will have a more modern
look and feel.
On Visual Studio, unlike MinGW, manifest files are embedded via
including the manifest file as a resource file in the projects, not
via the .rc file. This means that the line in the .rc file that
specifies the manifest file would cause trouble, so that line gets
removed when the full gtk3-win32.rc is generated on Visual Studio builds,
otherwise 2010+ Visual Studio will complain when compiling the .rc file.
Also, the inclusion of winuser.h will cause warnings during the
compilation of the .rc file.
Fix this by isolating the Win32 resource portions of gtk-win32.rc.in to
gtk-win32.rc.body.in and:
-On MinGW, construct the full gtk-win32.rc by doing the winver.h and
winuser.h inclusion first, then append the contents of gtk-win32.rc.body,
and then appending the line to embed the manifest file.
-On Visual Studio, simply copy the gtk-win32.rc.body to gtk-win32.rc,
and generate the full libgtk3.manifest file.
https://bugzilla.gnome.org/show_bug.cgi?id=762311
