Make base:ReplaceFile return an informative error.

base/file_util.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 "base/file_util.h"
 
 #if defined(OS_WIN)
 #include <io.h>
 #endif
 #include <stdio.h>
@@ skipping 45 matching lines @@
 
   value.insert(last_dot, suffix);
 }
 
 bool Move(const FilePath& from_path, const FilePath& to_path) {
   if (from_path.ReferencesParent() || to_path.ReferencesParent())
     return false;
   return MoveUnsafe(from_path, to_path);
 }
 
+bool ReplaceFile(const base::FilePath& from_path,
+                 const base::FilePath& to_path) {
+  return ReplaceFileAndGetError(from_path, to_path, NULL);
+}
+
 bool CopyFile(const FilePath& from_path, const FilePath& to_path) {
   if (from_path.ReferencesParent() || to_path.ReferencesParent())
     return false;
   return 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
   // doing anything smart with text formatting.
@@ skipping 206 matching lines @@
 // Note: the main logic is in file_util_<platform>.cc
 
 bool FileEnumerator::ShouldSkip(const FilePath& path) {
   FilePath::StringType basename = path.BaseName().value();
   return basename == FILE_PATH_LITERAL(".") ||
          (basename == FILE_PATH_LITERAL("..") &&
           !(INCLUDE_DOT_DOT & file_type_));
 }
 
 }  // namespace