Linux sandbox: cleanup sandbox-bpf naming.

sandbox/linux/seccomp-bpf/syscall.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 "sandbox/linux/seccomp-bpf/syscall.h"
 
 #include <asm/unistd.h>
 #include <errno.h>
 
 #include "base/basictypes.h"
 
-namespace playground2 {
+namespace sandbox {
 
   asm(      // We need to be able to tell the kernel exactly where we made a
             // system call. The C++ compiler likes to sometimes clone or
             // inline code, which would inadvertently end up duplicating
             // the entry point.
             // "gcc" can suppress code duplication with suitable function
             // attributes, but "clang" doesn't have this ability.
             // The "clang" developer mailing list suggested that the correct
             // and portable solution is a file-scope assembly block.
             // N.B. We do mark our code as a proper function so that backtraces
@@ skipping 210 matching lines @@
       );
     ret = inout;
   }
 #else
   errno = ENOSYS;
   intptr_t ret = -1;
 #endif
   return ret;
 }
 
-}  // namespace
+}  // namespace sandbox