[mutter] Make it possible to build without EGL support

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit bf42b54faaf3ec3c2f789467927d52003f60a79a
Author: Jonas Ådahl <jadahl gmail com>
Date:   Thu Aug 16 16:20:38 2018 +0200

    Make it possible to build without EGL support
    
    This will avoid building anything related to EGL. For meson, this will
    mean that both the native backend an the Wayland support must also be
    disabled.

 cogl/cogl/cogl-mutter.h                  | 2 ++
 cogl/cogl/cogl-texture-2d.c              | 2 ++
 cogl/cogl/driver/gl/cogl-texture-2d-gl.c | 4 ++++
 src/backends/x11/meta-renderer-x11.c     | 6 ++++++
 4 files changed, 14 insertions(+)
---
diff --git a/cogl/cogl/cogl-mutter.h b/cogl/cogl/cogl-mutter.h
index 13de039d0..0f1154e8a 100644
--- a/cogl/cogl/cogl-mutter.h
+++ b/cogl/cogl/cogl-mutter.h
@@ -39,7 +39,9 @@
 #include <cogl/cogl-error-private.h>
 #include <cogl/cogl-frame-info-private.h>
 #include <cogl/cogl-renderer-private.h>
+#if defined (COGL_HAS_EGL_SUPPORT)
 #include <cogl/winsys/cogl-winsys-egl-private.h>
+#endif
 #include <cogl/winsys/cogl-winsys-private.h>
 
 void cogl_renderer_set_custom_winsys (CoglRenderer                *renderer,
diff --git a/cogl/cogl/cogl-texture-2d.c b/cogl/cogl/cogl-texture-2d.c
index c0d14ed1e..65ba5114b 100644
--- a/cogl/cogl/cogl-texture-2d.c
+++ b/cogl/cogl/cogl-texture-2d.c
@@ -385,6 +385,7 @@ cogl_wayland_texture_2d_new_from_buffer (CoglContext *ctx,
       else
         return tex;
     }
+#ifdef COGL_HAS_EGL_SUPPORT
   else
     {
       int format, width, height;
@@ -439,6 +440,7 @@ cogl_wayland_texture_2d_new_from_buffer (CoglContext *ctx,
           return tex;
         }
     }
+#endif /* COGL_HAS_EGL_SUPPORT */
 
   _cogl_set_error (error,
                    COGL_SYSTEM_ERROR,
diff --git a/cogl/cogl/driver/gl/cogl-texture-2d-gl.c b/cogl/cogl/driver/gl/cogl-texture-2d-gl.c
index 56f8e34ef..ba90998ba 100644
--- a/cogl/cogl/driver/gl/cogl-texture-2d-gl.c
+++ b/cogl/cogl/driver/gl/cogl-texture-2d-gl.c
@@ -576,7 +576,11 @@ _cogl_texture_2d_gl_allocate (CoglTexture *tex,
     case COGL_TEXTURE_SOURCE_TYPE_GL_FOREIGN:
       return allocate_from_gl_foreign (tex_2d, loader, error);
     case COGL_TEXTURE_SOURCE_TYPE_EGL_IMAGE_EXTERNAL:
+#if defined (COGL_HAS_EGL_SUPPORT)
       return allocate_custom_egl_image_external (tex_2d, loader, error);
+#else
+      g_return_val_if_reached (FALSE);
+#endif
     }
 
   g_return_val_if_reached (FALSE);
diff --git a/src/backends/x11/meta-renderer-x11.c b/src/backends/x11/meta-renderer-x11.c
index 8a1183ecb..526861fa9 100644
--- a/src/backends/x11/meta-renderer-x11.c
+++ b/src/backends/x11/meta-renderer-x11.c
@@ -45,13 +45,19 @@ G_DEFINE_TYPE (MetaRendererX11, meta_renderer_x11, META_TYPE_RENDERER)
 static const CoglWinsysVtable *
 get_x11_cogl_winsys_vtable (CoglRenderer *renderer)
 {
+#ifdef COGL_HAS_EGL_PLATFORM_XLIB_SUPPORT
   if (meta_is_wayland_compositor ())
     return _cogl_winsys_egl_xlib_get_vtable ();
+#endif
 
   switch (renderer->driver)
     {
     case COGL_DRIVER_GLES2:
+#ifdef COGL_HAS_EGL_PLATFORM_XLIB_SUPPORT
       return _cogl_winsys_egl_xlib_get_vtable ();
+#else
+      break;
+#endif
     case COGL_DRIVER_GL:
     case COGL_DRIVER_GL3:
       return _cogl_winsys_glx_get_vtable ();