[gtk: 1/2] meson: Fix error when epoxy is a subproject on Windows

[Matthias Clasen <matthiasc src gnome org>]

commit fe89fd23172aa0b65e64fefc1104ba3581f63ef8
Author: Xavier Claessens <xavier claessens collabora com>
Date:   Wed Oct 14 17:26:23 2020 -0400

    meson: Fix error when epoxy is a subproject on Windows
    
    epoxy_dep cannot be used in a configure time check when it comes from a
    subproject. Use variables set in pc file instead.
    
    This requires https://github.com/anholt/libepoxy/pull/231.

 meson.build | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)
---
diff --git a/meson.build b/meson.build
index ce6b962f4c..0bed7b02fa 100644
--- a/meson.build
+++ b/meson.build
@@ -613,20 +613,10 @@ if win32_enabled
   backend_immodules += ['ime']
 
   # Check whether libepoxy is built with EGL support on Windows
-  win32_has_egl = cc.links(
-     '''
-     #include <epoxy/egl.h>
-        
-     int main(int argc, char *argv[])
-     {
-       EGLDisplay disp = EGL_NO_DISPLAY;
-
-       return epoxy_egl_version (disp);
-     } 
-     ''',
-     dependencies : epoxy_dep,
-     name : 'libepoxy supports EGL on Windows'
-    )
+  win32_has_egl = epoxy_dep.get_variable(
+    pkgconfig: 'epoxy_has_egl',
+    internal: 'epoxy_has_egl',
+    default_value: '0') == '1'
 endif
 
 # Check for bind_textdomain_codeset, including -lintl if GLib brings it in by