Remove onAsBinder() override for BackendUnifiedServiceManager

The implementation of onAsBinder was bypassing the
BackendUnifiedServiceManager when called in Java.

Test: N/A
Bug: 333854840
Flag: exempt. Bugfix
Change-Id: I0c364c3cb3c7ccbd59a3da041ec801357433479e

Author: parthsane

libs/binder/BackendUnifiedServiceManager.h

@@ -57,8 +57,6 @@ class BackendUnifiedServiceManager : public android::os::BnServiceManager {
         return mTheRealServiceManager->getInterfaceDescriptor();
     }
 
-    IBinder* onAsBinder() override { return IInterface::asBinder(mTheRealServiceManager).get(); }
-
 private:
     sp<os::IServiceManager> mTheRealServiceManager;
     void toBinderService(const os::Service& in, os::Service* _out);

libs/binder/tests/binderRpcUniversalTests.cpp

@@ -301,7 +301,8 @@ TEST_P(BinderRpc, CannotSendRegularBinderOverSocketBinder) {
 
     auto proc = createRpcTestSocketServerProcess({});
 
-    sp<IBinder> someRealBinder = IInterface::asBinder(defaultServiceManager());
+    sp<IBinder> someRealBinder = defaultServiceManager()->getService(String16("activity"));
+    ASSERT_NE(someRealBinder, nullptr);
     sp<IBinder> outBinder;
     EXPECT_EQ(INVALID_OPERATION,
               proc.rootIface->repeatBinder(someRealBinder, &outBinder).transactionError());