Cleanup: Remove some #defines that should already be in linux/magic.h.

base/files/file_util_linux.cc

Index: base/files/file_util_linux.cc
diff --git a/base/files/file_util_linux.cc b/base/files/file_util_linux.cc
index 532962f195c67b162b42f4fc791b9b1276b8bef5..b230fd96484c7d8e75f408edc912019d60ffb728 100644
--- a/base/files/file_util_linux.cc
+++ b/base/files/file_util_linux.cc
@@ -10,21 +10,6 @@
 
 #include "base/files/file_path.h"
 
-// Make sure some of the newer macros from magic.h are defined.
-// TODO(mostynb@opera.com): remove this after 2014.
-#ifndef BTRFS_SUPER_MAGIC
-#define BTRFS_SUPER_MAGIC 0x9123683E
-#endif
-#ifndef HUGETLBFS_MAGIC
-#define HUGETLBFS_MAGIC 0x958458f6
-#endif
-#ifndef RAMFS_MAGIC
-#define RAMFS_MAGIC 0x858458f6
-#endif
-#ifndef TMPFS_MAGIC
-#define TMPFS_MAGIC 0x01021994
-#endif
-
 namespace base {
 
 bool GetFileSystemType(const FilePath& path, FileSystemType* type) {