Move PathIsWritable, DirectoryExists, ContentsEqual, and TextContentsEqual to the base namespace.

TBR=sky

Review URL: https://codereview.chromium.org/19052005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@211675 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/component_updater/component_patcher_operation.cc b/chrome/browser/component_updater/component_patcher_operation.cc
index ba849189..3f5f46a 100644
--- a/chrome/browser/component_updater/component_patcher_operation.cc
+++ b/chrome/browser/component_updater/component_patcher_operation.cc
@@ -72,7 +72,7 @@
     return parse_result;
 
   const base::FilePath parent = output_abs_path_.DirName();
-  if (!file_util::DirectoryExists(parent)) {
+  if (!base::DirectoryExists(parent)) {
     if (!file_util::CreateDirectory(parent))
       return ComponentUnpacker::kIoError;
   }