Move some more file utils to the base namespace.

base/file_util_mac.mm

Index: base/file_util_mac.mm
diff --git a/base/file_util_mac.mm b/base/file_util_mac.mm
index 9d9ac3d99b42da1ef98868a85cff6f270c935041..f8a6b6301f5104a4b1d760a735b1a0949683a10e 100644
--- a/base/file_util_mac.mm
+++ b/base/file_util_mac.mm
@@ -23,9 +23,6 @@ bool CopyFileUnsafe(const FilePath& from_path, const FilePath& to_path) {
 }
 
 }  // namespace internal
-}  // namepsace base
-
-namespace file_util {
 
 bool GetTempDir(base::FilePath* path) {
   NSString* tmp = NSTemporaryDirectory();
@@ -35,8 +32,8 @@ bool GetTempDir(base::FilePath* path) {
   return true;
 }
 
-bool GetShmemTempDir(base::FilePath* path, bool executable) {
+bool GetShmemTempDir(bool executable, base::FilePath* path) {
   return GetTempDir(path);
 }
 
-}  // namespace
+}  // namespace base