Remove some unused NaCl srpc methods (AttachService, ctor variant)

components/nacl/renderer/plugin/srpc_client.cc

Index: components/nacl/renderer/plugin/srpc_client.cc
diff --git a/components/nacl/renderer/plugin/srpc_client.cc b/components/nacl/renderer/plugin/srpc_client.cc
index 58efd1a49fb6e315db96db351495422257c34870..4c9b4c919cbe318aac59fbad53475110fefff82e 100644
--- a/components/nacl/renderer/plugin/srpc_client.cc
+++ b/components/nacl/renderer/plugin/srpc_client.cc
@@ -191,9 +191,4 @@ bool SrpcClient::Invoke(const std::string& method_name, SrpcParams* params) {
   return true;
 }
 
-void SrpcClient::AttachService(NaClSrpcService* service, void* instance_data) {
-  srpc_channel_.server = service;
-  srpc_channel_.server_instance_data = instance_data;
-}
-
 }  // namespace plugin