Check if api modeling is enabled in class merger

Fixes: b/302074362
Change-Id: I6c9d7c17f87b9d7729293b02735955fa05739cd3
diff --git a/src/main/java/com/android/tools/r8/horizontalclassmerging/ClassMerger.java b/src/main/java/com/android/tools/r8/horizontalclassmerging/ClassMerger.java
index 507396f..06117ec 100644
--- a/src/main/java/com/android/tools/r8/horizontalclassmerging/ClassMerger.java
+++ b/src/main/java/com/android/tools/r8/horizontalclassmerging/ClassMerger.java
@@ -134,7 +134,10 @@
         newMethodReference.withName("$r8$clinit$synthetic", dexItemFactory);
     lensBuilder.recordNewMethodSignature(syntheticMethodReference, newMethodReference, true);
 
-    ComputedApiLevel apiReferenceLevel = classInitializerMerger.getApiReferenceLevel(appView);
+    ComputedApiLevel apiReferenceLevel =
+        appView.options().apiModelingOptions().isApiLibraryModelingEnabled()
+            ? classInitializerMerger.getApiReferenceLevel(appView)
+            : ComputedApiLevel.notSet();
     DexEncodedMethod definition =
         DexEncodedMethod.syntheticBuilder()
             .setMethod(newMethodReference)