Update from chromium https://crrev.com/302282

tools/vim/chromium.ycm_extra_conf.py

 # Copyright (c) 2012 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.
 
 # Autocompletion config for YouCompleteMe in Chromium.
 #
 # USAGE:
 #
 #   1. Install YCM [https://github.com/Valloric/YouCompleteMe]
 #          (Googlers should check out [go/ycm])
@@ skipping 22 matching lines @@
 #
 #   * That whole ninja & clang thing? We could support other configs if someone
 #     were willing to write the correct commands and a parser.
 #
 #   * This has only been tested on gPrecise.
 
 
 import os
 import os.path
 import subprocess
+import sys
 
 
 # Flags from YCM's default config.
 flags = [
 '-DUSE_CLANG_COMPLETER',
 '-std=c++11',
 '-x',
 'c++',
 ]
 
@@ skipping 17 matching lines @@
   while not (PathExists(curdir, 'src') and PathExists(curdir, 'src', 'DEPS')
              and (PathExists(curdir, '.gclient')
                   or PathExists(curdir, 'src', '.git'))):
     nextdir = os.path.normpath(os.path.join(curdir, '..'))
     if nextdir == curdir:
       return None
     curdir = nextdir
   return os.path.join(curdir, 'src')
 
 
-# Largely copied from ninja-build.vim (guess_configuration)
-def GetNinjaOutputDirectory(chrome_root):
-  """Returns <chrome_root>/<output_dir>/(Release|Debug).
-
-  The configuration chosen is the one most recently generated/built. Detects
-  a custom output_dir specified by GYP_GENERATOR_FLAGS."""
-
-  output_dir = 'out'
-  generator_flags = os.getenv('GYP_GENERATOR_FLAGS', '').split(' ')
-  for flag in generator_flags:
-    name_value = flag.split('=', 1)
-    if len(name_value) == 2 and name_value[0] == 'output_dir':
-      output_dir = name_value[1]
-
-  root = os.path.join(chrome_root, output_dir)
-  debug_path = os.path.join(root, 'Debug')
-  release_path = os.path.join(root, 'Release')
-
-  def is_release_15s_newer(test_path):
-    try:
-      debug_mtime = os.path.getmtime(os.path.join(debug_path, test_path))
-    except os.error:
-      debug_mtime = 0
-    try:
-      rel_mtime = os.path.getmtime(os.path.join(release_path, test_path))
-    except os.error:
-      rel_mtime = 0
-    return rel_mtime - debug_mtime >= 15
-
-  if is_release_15s_newer('build.ninja') or is_release_15s_newer('protoc'):
-    return release_path
-  return debug_path
-
-
 def GetClangCommandFromNinjaForFilename(chrome_root, filename):
   """Returns the command line to build |filename|.
 
   Asks ninja how it would build the source file. If the specified file is a
   header, tries to find its companion source file first.
 
   Args:
     chrome_root: (String) Path to src/.
     filename: (String) Path to source file being edited.
 
@@ skipping 35 matching lines @@
     else:
       if filename.startswith(blink_root):
         # If this is a Blink file, we can at least try to get a reasonable
         # approximation.
         filename = default_blink_file
       else:
         # If this is a standalone .h file with no source, the best we can do is
         # try to use the default flags.
         return chrome_flags
 
+  sys.path.append(os.path.join(chrome_root, 'tools', 'vim'))
+  from ninja_output import GetNinjaOutputDirectory
   out_dir = os.path.realpath(GetNinjaOutputDirectory(chrome_root))
 
   # Ninja needs the path to the source file relative to the output build
   # directory.
   rel_filename = os.path.relpath(os.path.realpath(filename), out_dir)
 
   # Ask ninja how it would build our source file.
   p = subprocess.Popen(['ninja', '-v', '-C', out_dir, '-t',
                         'commands', rel_filename + '^'],
                        stdout=subprocess.PIPE)
@@ skipping 46 matching lines @@
   """
   chrome_root = FindChromeSrcFromFilename(filename)
   chrome_flags = GetClangCommandFromNinjaForFilename(chrome_root,
                                                      filename)
   final_flags = flags + chrome_flags
 
   return {
     'flags': final_flags,
     'do_cache': True
   }