 no longer valid.
        </p>
        <p>
            <code class="constant">EGL_BAD_NATIVE_WINDOW</code> may be generated if
            a native window underlying either
            <em class="parameter"><code>draw</code></em> or
            <em class="parameter"><code>read</code></em>
            is no longer valid.
        </p>
        <p>
            <code class="constant">EGL_BAD_CURRENT_SURFACE</code> is generated if
            the previous context has unflushed commands and the previous surface
  