Fix getcwd for bionic.

Experimental bionic toolchain had incorrect definition for getcwd.
This change only affects the experimental build of NaCl SDK.

BUG=none
R=binji@chromium.org
TEST=build_sdk.py

Review URL: https://codereview.chromium.org/233773002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263149 0039d316-1c4b-4281-b951-d872f2087c98

native_client_sdk/src/libraries/nacl_io/kernel_wrap_bionic.cc

@@ -197,7 +197,7 @@ 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;