The UI language rather than the locale is now used to pick Chrome's language ...

chrome/installer/util/prebuild/create_string_rc.py

Index: chrome/installer/util/prebuild/create_string_rc.py
===================================================================
--- chrome/installer/util/prebuild/create_string_rc.py	(revision 65433)
+++ chrome/installer/util/prebuild/create_string_rc.py	(working copy)
@@ -175,6 +175,7 @@
   """Writes a .h file with resource ids.  This file can be included by the
   executable to refer to identifiers."""
   lines = []
+  do_languages_lines = [u'#define DO_LANGUAGES']
 
   # Write the values for how the languages ids are offset.
   seen_languages = set()
@@ -184,6 +185,8 @@
     if lang not in seen_languages:
       seen_languages.add(lang)
       lines.append(u'#define IDS_L10N_OFFSET_%s %s' % (lang, offset_id))
+      do_languages_lines.append(u'  HANDLE_LANGUAGE(%s, IDS_L10N_OFFSET_%s)'
+                                % (lang.replace('_', '-').lower(), lang))

[robertshield, 2010/11/11 14:42:18]

why are these strings unicode strings, but not the ones below?

[grt (UTC plus 2), 2010/11/11 15:23:57]

Your guess is as good as mine.  erikwright@chromium.org, who is wise in the ways
of Python, tells me it's okay as is, but odd; possibly the result of multiple
people editing and not keeping track of things, or possibly to handle corner
cases involving Unicode and non-Unicode strings.  All language tags are ASCII,
so all should be well.  Would you like me to make all of the strings Unicode in
this file?

[robertshield, 2010/11/11 16:18:53]

They should be consistent. Inconsistencies like this make people wonder whether
there's a motive behind them. 

If none of the strings need to be unicode, lets make them all ascii. If some
need to be unicode, lets make them all that way.

[grt (UTC plus 2), 2010/11/11 16:29:27]

Done.

       offset_id += 1
     else:
       break
@@ -203,7 +206,10 @@
 
   outfile = open(out_filename + '.h', 'wb')
   outfile.write('\n'.join(lines))
-  outfile.write('\n')  # .rc files must end in a new line
+  outfile.write('\n#ifndef RC_INVOKED\n')
+  outfile.write(' \\\n'.join(do_languages_lines))
+  # .rc files must end in a new line
+  outfile.write('\n#endif  // ndef RC_INVOKED\n')
   outfile.close()
 
 def main(argv):