egl: set context version when egl < 1.5

CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Fixed EGL not setting context version with EGL versions before 1.5 and missing context ext.
+
 # Version 0.31.1
 
 - Fixed `CGLContextObj` having an invalid encoding on newer macOS versions.

glutin/src/api/egl/context.rs

@@ -117,6 +117,13 @@ impl Display {
                 attrs.push(egl::CONTEXT_FLAGS_KHR as EGLint);
                 attrs.push(flags as EGLint);
             }
+        } else if self.inner.version >= Version::new(1, 3) {
+            // EGL 1.3 uses that to indicate client version instead of major/minor. The
+            // constant is the same as `CONTEXT_MAJOR_VERSION`.
+            if let Some(version) = version {
+                attrs.push(egl::CONTEXT_CLIENT_VERSION as EGLint);
+                attrs.push(version.major as EGLint);
+            }
         }
 
         attrs.push(egl::NONE as EGLint);