Update monet.

tools/vim/mojom/ftdetect/mojomfiletype.vim

+" Copyright 2015 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.
+" We take care to preserve the user's fileencodings and fileformats,
+" because those settings are global (not buffer local), yet we want
+" to override them for loading mojom files, which should be UTF-8.
+"
+let s:current_fileformats = ''
+let s:current_fileencodings = ''
+
+" define fileencodings to open as utf-8 encoding even if it's ascii.
+function! s:mojomfiletype_pre()
+  let s:current_fileformats = &g:fileformats
+  let s:current_fileencodings = &g:fileencodings
+  set fileencodings=utf-8 fileformats=unix
+  setlocal filetype=mojom
+endfunction
+
+" restore fileencodings as others
+function! s:mojomfiletype_post()
+  let &g:fileformats = s:current_fileformats
+  let &g:fileencodings = s:current_fileencodings
+endfunction
+
+au BufNewFile *.mojom setlocal filetype=mojom fileencoding=utf-8 fileformat=unix
+au BufRead *.mojom call s:mojomfiletype_pre()
+au BufReadPost *.mojom call s:mojomfiletype_post()