Patched to compile on OpenGL ES-based platforms.

src/video/SDL_video.c

@@ -46,6 +46,10 @@
 #include "SDL_opengles2.h"
 #endif /* SDL_VIDEO_OPENGL_ES2 && !SDL_VIDEO_OPENGL */
 
+#ifndef GL_CONTEXT_RELEASE_BEHAVIOR_KHR
+#define GL_CONTEXT_RELEASE_BEHAVIOR_KHR 0x82FB
+#endif
+
 /* On Windows, windows.h defines CreateWindow */
 #ifdef CreateWindow
 #undef CreateWindow