Remove NaClPluginLowLevelInitializationComplete() (caller of "init_done" SRPC)

src/shared/srpc/BUILD.gn

 # Copyright (c) 2014 The Native ClientAuthors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 static_library("nonnacl_srpc") {
   deps = [
     "//native_client/build/config/nacl:nacl_base",
   ]
 
   sources = [
@@ skipping 19 matching lines @@
       "//native_client/src/untrusted/nacl:imc_syscalls",
     ]
 
     sources = [
       "accept.c",
       "accept_threaded.c",
       "invoke.c",
       "module_init_fini.c",
       "nacl_srpc.c",
       "nacl_srpc_message.c",
-      "nacl_srpc_ppapi_plugin_init.c",
-      "nacl_srpc_ppapi_plugin_internal.c",
       "rpc_log.c",
       "rpc_serialize.c",
       "rpc_server_loop.c",
       "rpc_service.c",
     ]
 
     cflags_c = [
       "-fno-strict-aliasing",
     ]
   }
 }