Clean more legacy code (#3478)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

test/renderer/shader_registry.test.cpp

@@ -21,7 +21,10 @@
 #include <mbgl/gfx/backend_scope.hpp>
 #include <mbgl/gfx/headless_frontend.hpp>
 #include <mbgl/test/map_adapter.hpp>
-#include <mbgl/programs/clipping_mask_program.hpp>
+
+#ifdef MLN_RENDER_BACKEND_OPENGL
+#include <mbgl/shaders/gl/legacy/clipping_mask_program.hpp>
+#endif
 
 using namespace mbgl;
 
@@ -206,6 +209,7 @@ TEST(ShaderRegistry, NamedReplace) {
     ASSERT_NE(progA, progB);
 }
 
+#ifdef MLN_RENDER_BACKEND_OPENGL
 // Test replacing an actual program instance with a similar instance
 TEST(ShaderRegistry, DISABLED_GLSLReplacement_NoOp) {
     MapInstance::ShaderAndStyleObserver observer;
@@ -323,3 +327,4 @@ void main() {
     auto img = map.frontend.render(map.adapter).image;
     test::checkImage("test/fixtures/shader_registry/glsl_replace_2", img, 0.005, 0.1);
 }
+#endif // MLN_RENDER_BACKEND_OPENGL