Unbreak unit tests. Revert r7564.

base/file_util.cc

Index: base/file_util.cc
===================================================================
--- base/file_util.cc	(revision 7570)
+++ base/file_util.cc	(working copy)
@@ -79,13 +79,12 @@
     dir->resize(dir->length() - 1);
 }
 
-FilePath::StringType GetFileExtensionFromPath(const FilePath& path) {
-  FilePath::StringType file_name = path.BaseName().value();
-  const FilePath::StringType::size_type last_dot =
-      file_name.rfind(kExtensionSeparator);
-  return FilePath::StringType(last_dot == FilePath::StringType::npos ?
-                              FILE_PATH_LITERAL("") : 
-                              file_name, last_dot+1);
+std::wstring GetFileExtensionFromPath(const std::wstring& path) {
+  std::wstring file_name = GetFilenameFromPath(path);
+  std::wstring::size_type last_dot = file_name.rfind(L'.');
+  return std::wstring(last_dot == std::wstring::npos ? 
+      L"" : 
+      file_name, last_dot+1);
 }
 
 std::wstring GetFilenameWithoutExtensionFromPath(const std::wstring& path) {
@@ -375,15 +374,6 @@
   *path_str = path.ToWStringHack();
   return true;
 }
-std::wstring GetFileExtensionFromPath(const std::wstring& path) {
-  FilePath::StringType extension =
-    GetFileExtensionFromPath(FilePath::FromWStringHack(path));
-#if defined(OS_WIN)
-  return extension;
-#elif defined(OS_POSIX)
-  return UTF8ToWide(extension);
-#endif
-}
 bool GetFileInfo(const std::wstring& file_path, FileInfo* results) {
   return GetFileInfo(FilePath::FromWStringHack(file_path), results);
 }
@@ -391,7 +381,11 @@
   if (path.empty() || EndsWithSeparator(path))
     return std::wstring();
 
-  return FilePath::FromWStringHack(path).BaseName().ToWStringHack();
+#if defined(OS_WIN)
+  return FilePath::FromWStringHack(path).BaseName();
+#elif defined(OS_POSIX)
+  return UTF8ToWide(FilePath::FromWStringHack(path).BaseName());
+#endif
 }
 bool GetFileSize(const std::wstring& file_path, int64* file_size) {
   return GetFileSize(FilePath::FromWStringHack(file_path), file_size);