Apply missing kParentDirectory check

BUG=161564

Review URL: https://chromiumcodereview.appspot.com/11414046

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@168692 0039d316-1c4b-4281-b951-d872f2087c98
bool ChildProcessSecurityPolicyImpl::CanReadDirectory(
    int child_id, const FilePath& directory) {
  return HasPermissionsForFile(child_id,
                               directory,
                               kEnumerateDirectoryPermissions);
}

bool ChildProcessSecurityPolicyImpl::CanReadDirectory(
    int child_id, const FilePath& directory) {
  return HasPermissionsForFile(child_id,
                               directory,
                               kEnumerateDirectoryPermissions);
}
