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

app/l10n_util_win.cc

Index: app/l10n_util_win.cc
===================================================================
--- app/l10n_util_win.cc	(revision 66182)
+++ app/l10n_util_win.cc	(working copy)
@@ -2,14 +2,17 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "app/l10n_util.h"
+#include "app/l10n_util_win.h"
 
+#include <windowsx.h>
 #include <algorithm>
-#include <windowsx.h>
+#include <iterator>
 
-#include "app/l10n_util_win.h"
+#include "app/l10n_util.h"
 #include "base/i18n/rtl.h"
+#include "base/lazy_instance.h"
 #include "base/string_number_conversions.h"
+#include "base/win/i18n.h"
 #include "base/win/windows_version.h"
 #include "grit/app_locale_settings.h"
 
@@ -52,6 +55,21 @@
   return wcscmp(font_name, actual_font_name) == 0;
 }
 
+class OverrideLocaleHolder {
+ public:
+  OverrideLocaleHolder() {}
+  const std::vector<std::string>& value() const { return value_; }
+  void swap_value(std::vector<std::string>* override_value) {
+    value_.swap(*override_value);
+  }
+ private:
+  std::vector<std::string> value_;
+  DISALLOW_COPY_AND_ASSIGN(OverrideLocaleHolder);
+};
+
+base::LazyInstance<OverrideLocaleHolder>
+    override_locale_holder(base::LINKER_INITIALIZED);
+
 }  // namespace
 
 namespace l10n_util {
@@ -147,4 +165,21 @@
   }
 }
 
+void OverrideLocaleWithUILanguageList() {
+  std::vector<std::wstring> ui_languages;
+  if (base::win::i18n::GetThreadPreferredUILanguageList(&ui_languages)) {
+    std::vector<std::string> ascii_languages;
+    ascii_languages.reserve(ui_languages.size());
+    std::transform(ui_languages.begin(), ui_languages.end(),
+                   std::back_inserter(ascii_languages), &WideToASCII);
+    override_locale_holder.Get().swap_value(&ascii_languages);
+  } else {
+    NOTREACHED() << "Failed to determine the UI language for locale override.";
+  }
+}
+
+const std::vector<std::string>& GetLocaleOverrides() {
+  return override_locale_holder.Get().value();
+}
+
 }  // namespace l10n_util