Update from chromium https://crrev.com/304586

base/files/file_util.cc

Index: base/files/file_util.cc
diff --git a/base/files/file_util.cc b/base/files/file_util.cc
index e60dcd9d346df70f5387051a072bcc8389eaf590..32dab6bd40d8ee6b0113522259a8b2ff123f5712 100644
--- a/base/files/file_util.cc
+++ b/base/files/file_util.cc
@@ -47,12 +47,6 @@ bool Move(const FilePath& from_path, const FilePath& to_path) {
   return internal::MoveUnsafe(from_path, to_path);
 }
 
-bool CopyFile(const FilePath& from_path, const FilePath& to_path) {
-  if (from_path.ReferencesParent() || to_path.ReferencesParent())
-    return false;
-  return internal::CopyFileUnsafe(from_path, to_path);
-}
-
 bool ContentsEqual(const FilePath& filename1, const FilePath& filename2) {
   // We open the file in binary format even if they are text files because
   // we are just comparing that bytes are exactly same in both files and not