Fix gldemo

The GL program needs to be used before accessing its attributes.

#minor-release

PiperOrigin-RevId: 410768017

demos/gl/src/main/java/com/google/android/exoplayer2/gldemo/BitmapOverlayVideoProcessor.java

@@ -88,6 +88,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     } catch (IOException e) {
     } catch (IOException e) {
       throw new IllegalStateException(e);
       throw new IllegalStateException(e);
     }
     }
+    program.use();
     GlUtil.Attribute[] attributes = program.getAttributes();
     GlUtil.Attribute[] attributes = program.getAttributes();
     for (GlUtil.Attribute attribute : attributes) {
     for (GlUtil.Attribute attribute : attributes) {
       if (attribute.name.equals("a_position")) {
       if (attribute.name.equals("a_position")) {
@@ -142,7 +143,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     // Run the shader program.
     // Run the shader program.
     GlUtil.Uniform[] uniforms = checkNotNull(this.uniforms);
     GlUtil.Uniform[] uniforms = checkNotNull(this.uniforms);
     GlUtil.Attribute[] attributes = checkNotNull(this.attributes);
     GlUtil.Attribute[] attributes = checkNotNull(this.attributes);
-    checkNotNull(program).use();
     for (GlUtil.Uniform uniform : uniforms) {
     for (GlUtil.Uniform uniform : uniforms) {
       switch (uniform.name) {
       switch (uniform.name) {
         case "tex_sampler_0":
         case "tex_sampler_0":