Plumbing though mode parameter to open, since fusefs can make use of it.

native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h

Index: native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h
diff --git a/native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h b/native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h
index ea136ebf96aacdf0f0ca5b1071c6b99101431433..d9f77c78e1df89bf3c1859d84233715fe837ddd1 100644
--- a/native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h
+++ b/native_client_sdk/src/libraries/nacl_io/stream/stream_fs.h
@@ -54,7 +54,8 @@ class StreamFs : public Filesystem {
   // of a MountSocketWork object.
   static PP_CompletionCallback GetRunCompletion(Work* work);
 
-  virtual Error Open(const Path& path, int o_flags, ScopedNode* out_node);
+  virtual Error OpenWithMode(const Path& path, int o_flags, mode_t mode,
+                             ScopedNode* out_node);
   virtual Error Unlink(const Path& path);
   virtual Error Mkdir(const Path& path, int permissions);
   virtual Error Rmdir(const Path& path);