Fix security vulnerability am: 2ae83f4f am: 11ab5838 am: ac2b87ac am: 132d0f2a

        if (s.client != NULL) {

            sp<IBinder> binder = s.client->asBinder();

            if (binder != NULL) {

                String16 desc(binder->getInterfaceDescriptor());

                if (desc == ISurfaceComposerClient::descriptor) {

                if (binder->queryLocalInterface(ISurfaceComposerClient::descriptor) != NULL) {

                    sp<Client> client( static_cast<Client *>(s.client.get()) );

                    transactionFlags |= setClientStateLocked(client, s.state);

                }