A build fix for Mac GCC.

net/base/file_stream_posix.cc

Index: net/base/file_stream_posix.cc
===================================================================
--- net/base/file_stream_posix.cc	(revision 106893)
+++ net/base/file_stream_posix.cc	(working copy)
@@ -105,6 +105,8 @@
   return res;
 }
 
+}  // namespace
+
 // Cancelable wrapper around a Closure.
 class CancelableCallback {
  public:
@@ -126,8 +128,6 @@
   const base::Closure callback_;
 };
 
-}  // namespace
-
 // FileStream::AsyncContext ----------------------------------------------
 
 class FileStream::AsyncContext {