remove changing class version

Author: laurit

javaagent-tooling/build.gradle.kts

@@ -103,17 +103,6 @@ testing {
       }
     }
 
-    val testPatchBytecodeVersion by registering(JvmTestSuite::class) {
-      dependencies {
-        implementation(project(":javaagent-bootstrap"))
-        implementation(project(":javaagent-tooling"))
-        implementation("net.bytebuddy:byte-buddy-dep")
-
-        // Used by byte-buddy but not brought in as a transitive dependency.
-        compileOnly("com.google.code.findbugs:annotations")
-      }
-    }
-
     val testConfigFile by registering(JvmTestSuite::class) {
       dependencies {
         implementation(project(":javaagent-tooling"))

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/instrumentation/InstrumentationModuleInstaller.java

@@ -28,7 +28,6 @@
 import io.opentelemetry.javaagent.tooling.instrumentation.indy.ForwardIndyAdviceTransformer;
 import io.opentelemetry.javaagent.tooling.instrumentation.indy.IndyModuleRegistry;
 import io.opentelemetry.javaagent.tooling.instrumentation.indy.IndyTypeTransformerImpl;
-import io.opentelemetry.javaagent.tooling.instrumentation.indy.PatchByteCodeVersionTransformer;
 import io.opentelemetry.javaagent.tooling.muzzle.HelperResourceBuilderImpl;
 import io.opentelemetry.javaagent.tooling.muzzle.InstrumentationModuleMuzzle;
 import io.opentelemetry.javaagent.tooling.util.IgnoreFailedTypeMatcher;
@@ -146,23 +145,13 @@ private AgentBuilder installIndyModule(
     VirtualFieldImplementationInstaller contextProvider =
         virtualFieldInstallerFactory.create(instrumentationModule);
 
-    boolean allowClassVersionChange =
-        config.getBoolean("otel.javaagent.experimental.allow-class-version-change", false);
     AgentBuilder agentBuilder = parentAgentBuilder;
     for (TypeInstrumentation typeInstrumentation : instrumentationModule.typeInstrumentations()) {
-      AgentBuilder.Identified.Extendable extendableAgentBuilder;
-      AgentBuilder.Identified.Narrowable narrowableAgentBuilder =
+      AgentBuilder.Identified.Extendable extendableAgentBuilder =
           setTypeMatcher(agentBuilder, instrumentationModule, typeInstrumentation)
-              .and(muzzleMatcher);
-      if (allowClassVersionChange) {
-        extendableAgentBuilder =
-            narrowableAgentBuilder.transform(new PatchByteCodeVersionTransformer());
-      } else {
-        extendableAgentBuilder =
-            narrowableAgentBuilder
-                .transform(ConstantAdjuster.instance())
-                .transform(new ForwardIndyAdviceTransformer(helperInjector));
-      }
+              .and(muzzleMatcher)
+              .transform(ConstantAdjuster.instance())
+              .transform(new ForwardIndyAdviceTransformer(helperInjector));
 
       extendableAgentBuilder =
           IndyModuleRegistry.initializeModuleLoaderOnMatch(