[NaCl SDK] Add nacl_io and sdk_util namespaces.

native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc

Index: native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc b/native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc
index 462e1a3de6f51cae003a346beab7110be71cba50..42731398b7c0152102654172bc476919c8a5c58e 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_proxy.cc
@@ -33,9 +33,7 @@
 #define MAXPATHLEN 256
 #endif
 
-// TODO(noelallen) : Grab/Redefine these in the kernel object once available.
-#define USR_ID 1002
-#define GRP_ID 1003
+namespace nacl_io {
 
 KernelProxy::KernelProxy() : dev_(0), ppapi_(NULL) {
 }
@@ -642,3 +640,5 @@ int KernelProxy::munmap(void* addr, size_t length) {
   return 0;
 }
 
+}  // namespace nacl_io
+