Limit instrumentation on interfaces

Previously, Robolectric enabled some of its instrumentation on interfaces
in order to support hooking up interceptors on default interface methods.
This is because there are now some default interface methods that invoke
System.logW (e.g. android.compat.Compatibility$BehaviorChangeDelegate)

However, the instrumentation step that makes classes public
was also applied to interfaces, and this seems to confuse Mockito/ByteBuddy,
but only in certain environments.

As a fix, restrict the instrumentation to only rewrite interface method
bodies, as well as extends 'InstrumentedInterface', so Robolectric does
not re-instrument interfaces when the preinstrumented jars are used.

A test case will be added after the preinstrumented jar version is
bumped.

Fixes #6858

PiperOrigin-RevId: 410440888

sandbox/src/main/java/org/robolectric/internal/bytecode/ClassInstrumentor.java

@@ -143,18 +143,6 @@ private void recordPackageStats(PerfStatsCollector perfStats, MutableClass mutab
 
   public void instrument(MutableClass mutableClass) {
     try {
-      makeClassPublic(mutableClass.classNode);
-      if ((mutableClass.classNode.access & Opcodes.ACC_FINAL) == Opcodes.ACC_FINAL) {
-        mutableClass
-            .classNode
-            .visitAnnotation("Lcom/google/errorprone/annotations/DoNotMock;", true)
-            .visit(
-                "value",
-                "This class is final. Consider using the real thing, or "
-                    + "adding/enhancing a Robolectric shadow for it.");
-      }
-      mutableClass.classNode.access = mutableClass.classNode.access & ~Opcodes.ACC_FINAL;
-
       // Need Java version >=7 to allow invokedynamic
       mutableClass.classNode.version = Math.max(mutableClass.classNode.version, Opcodes.V1_7);
 
@@ -163,6 +151,18 @@ public void instrument(MutableClass mutableClass) {
       if (mutableClass.isInterface()) {
         mutableClass.addInterface(Type.getInternalName(InstrumentedInterface.class));
       } else {
+        makeClassPublic(mutableClass.classNode);
+        if ((mutableClass.classNode.access & Opcodes.ACC_FINAL) == Opcodes.ACC_FINAL) {
+          mutableClass
+              .classNode
+              .visitAnnotation("Lcom/google/errorprone/annotations/DoNotMock;", true)
+              .visit(
+                  "value",
+                  "This class is final. Consider using the real thing, or "
+                      + "adding/enhancing a Robolectric shadow for it.");
+        }
+        mutableClass.classNode.access = mutableClass.classNode.access & ~Opcodes.ACC_FINAL;
+
         // If there is no constructor, adds one
         addNoArgsConstructor(mutableClass);