If CreateDirectory() fails during extension unpacking, log the exact OS call that failed.

base/file_util.h

 // Copyright (c) 2010 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.
 
 // This file contains utility functions for dealing with the local
 // filesystem.
 
 #ifndef BASE_FILE_UTIL_H_
 #define BASE_FILE_UTIL_H_
 
@@ skipping 263 matching lines @@
 // TODO(erikkay): is this OK?
 // If success, return true and output the full path of the directory created.
 bool CreateNewTempDirectory(const FilePath::StringType& prefix,
                             FilePath* new_temp_path);
 
 // Creates a directory, as well as creating any parent directories, if they
 // don't exist. Returns 'true' on successful creation, or if the directory
 // already exists.  The directory is only readable by the current user.
 bool CreateDirectory(const FilePath& full_path);
 
+#if defined(OS_WIN)
+// Added for debugging an issue where CreateDirectory() fails.  LOG(*) does
+// not work, because the failure happens in a sandboxed process.
+// TODO(skerner): Remove once crbug/35198 is resolved.
+bool CreateDirectoryExtraLogging(const FilePath& full_path,
+                                 std::ostream& error);
+#endif  // defined (OS_WIN)
+
 // Returns the file size. Returns true on success.
 bool GetFileSize(const FilePath& file_path, int64* file_size);
 
 // Returns true if the given path's base name is ".".
 bool IsDot(const FilePath& path);
 
 // Returns true if the given path's base name is "..".
 bool IsDotDot(const FilePath& path);
 
 // Sets |real_path| to |path| with symbolic links and junctions expanded.
@@ skipping 294 matching lines @@
 
 #endif  // UNIT_TEST
 
 }  // namespace file_util
 
 // Deprecated functions have been moved to this separate header file,
 // which must be included last after all the above definitions.
 #include "base/file_util_deprecated.h"
 
 #endif  // BASE_FILE_UTIL_H_