drive: Use "/drive/root" namespace and fix Files app and tests.

chrome/browser/chromeos/drive/change_list_loader.cc

Index: chrome/browser/chromeos/drive/change_list_loader.cc
diff --git a/chrome/browser/chromeos/drive/change_list_loader.cc b/chrome/browser/chromeos/drive/change_list_loader.cc
index d028c72c8323b85fdffb3e028064c643da9dcadf..731c0b5860557e1bdb638acf0290b91c929d1cf4 100644
--- a/chrome/browser/chromeos/drive/change_list_loader.cc
+++ b/chrome/browser/chromeos/drive/change_list_loader.cc
@@ -219,10 +219,12 @@ void ChangeListLoader::CompareChangestampsAndLoadIfNeeded(
     LoadChangeListFromServer(about_resource.Pass(),
                              start_changestamp,
                              callback);
-  } else if (directory_fetch_info.changestamp() < remote_changestamp) {
+  } else if (directory_fetch_info.changestamp() < remote_changestamp &&
+             !util::IsSpecialResourceId(directory_fetch_info.resource_id())) {
     // If the caller is interested in a particular directory, and the
     // directory changestamp is older than server's, start loading the
-    // directory first.
+    // directory first. Skip special entries as they are not meaningful in the
+    // server.
     DVLOG(1) << "Fast-fetching directory: " << directory_fetch_info.ToString()
              << "; remote_changestamp: " << remote_changestamp;
     const DirectoryFetchInfo new_directory_fetch_info(