Otherwise there will be a warning:
"libEGL warning: FIXME: egl/x11 doesn't support front buffer rendering."
Happens with EGL_KHR_surfaceless_context:
eglMakeCurrent(egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE, egl_context) eglMakeCurrent(egl_display, egl_surface, egl_surface, egl_context) glFlush() // Here will be a warning
Closes: #1525 (closed)
I also think that it's a bit weird that
_mesa_is_front_buffer_drawing1 returns true for
IncompleteFramebuffer maybe it should return false for it, but it felt like too big change for something that's not really broken.