[NaCl SDK] Fix getcwd for bionic.

native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <sys/types.h>  // Include something that will define __BIONIC__.
 
 // The entire file is wrapped in this #if. We do this so this .cc file can be
 // compiled, even on a non-bionic build.
 
 #if defined(__native_client__) && defined(__BIONIC__)
@@ skipping 179 matching lines @@
   if (res < 0)
     return errno;
   stat_to_nacl_stat(&buf, nacl_buf);
   return 0;
 }
 
 int WRAP(fsync)(int fd) NOTHROW {
   return (ki_fsync(fd)) ? errno : 0;
 }
 
-char* WRAP(getcwd)(char* buf, size_t size) {
+int WRAP(getcwd)(char* buf, size_t size) {
   if (ki_getcwd(buf, size) == NULL)
     return errno;
   return 0;
 }
 
 int WRAP(getdents)(int fd, dirent* nacl_buf, size_t nacl_count, size_t *nread) {
   int nacl_offset = 0;
   // "buf" contains dirent(s); "nacl_buf" contains nacl_abi_dirent(s).
   // nacl_abi_dirent(s) are smaller than dirent(s), so nacl_count bytes buffer
   // is enough
@@ skipping 300 matching lines @@
 void kernel_wrap_uninit() {
   if (s_wrapped) {
     EXPAND_SYMBOL_LIST_OPERATION(USE_REAL)
     s_wrapped = false;
   }
 }
 
 EXTERN_C_END
 
 #endif  // defined(__native_client__) && defined(__GLIBC__)