Use GetDefaultLocaleListString for returning LocaleList

android_webview/browser/aw_content_browser_client.cc

 // 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.
 
 #include "android_webview/browser/aw_content_browser_client.h"
 
 #include <utility>
 
 #include "android_webview/browser/aw_browser_context.h"
 #include "android_webview/browser/aw_browser_main_parts.h"
@@ skipping 140 matching lines @@
 void AwContentsMessageFilter::OnSubFrameCreated(int parent_render_frame_id,
                                                 int child_render_frame_id) {
   AwContentsIoThreadClient::SubFrameCreated(
       process_id_, parent_render_frame_id, child_render_frame_id);
 }
 
 AwLocaleManager* g_locale_manager = NULL;
 
 }  // anonymous namespace
 
+// TODO(yirui): could use similar logic as in
+//              PrependToAcceptLanguagesIfNecessary
+//              in chrome/browser/android/preferences/pref_service_bridge.cc
 // static
 std::string AwContentBrowserClient::GetAcceptLangsImpl() {

[Seigo Nonaka, 2016/11/15 05:15:59]

Question: Is there no unit tests for this function? If no, how about adding test
cases for making sure this change keeps existing behaviors.

[Yirui Huang, 2016/11/16 00:23:45]

Done.

-  // Start with the current locale.
-  std::string langs = g_locale_manager->GetLocale();
+  // Start with the current locale(s).
+  std::string locales_string = g_locale_manager->GetLocales();
 
-  // If we're not en-US, add in en-US which will be
+  // If accept languages do not contain en-US, add in en-US which will be
   // used with a lower q-value.
-  if (base::ToLowerASCII(langs) != "en-us") {
-    langs += ",en-US";
-  }
-  return langs;
+  size_t found_enUS = locales_string.find("en-US");

[Seigo Nonaka, 2016/11/15 05:15:59]

Question: do we no longer need to compare in case insensitively?

[Yirui Huang, 2016/11/16 00:23:45]

I thought locales_string that we got from here is from
LocaleUtils.getDefaultLocaleListString, which returns a well formed BCP47 form.
Added lower case checking just in case.

[Seigo Nonaka, 2016/11/16 01:26:14]

Please note that developer can set accept language manually in Android WebView.
Please see what happens when developer passes not well-formed BCP47 locale
string.

c.f.
http://stackoverflow.com/questions/12244375/how-can-i-override-android-webvie...

[Yirui Huang, 2016/11/16 01:49:12]

I see. Thanks for pointing this out. I wasn't aware of developer side.

+  if (found_enUS == std::string::npos)
+    locales_string += ",en-US";
+  return locales_string;
 }
 
 // static
 AwBrowserContext* AwContentBrowserClient::GetAwBrowserContext() {
   return AwBrowserContext::GetDefault();
 }
 
 AwContentBrowserClient::AwContentBrowserClient(
     JniDependencyFactory* native_factory)
     : native_factory_(native_factory) {
@@ skipping 352 matching lines @@
   if (id == -1)
     return nullptr;
 
   base::StringPiece manifest_contents =
       ui::ResourceBundle::GetSharedInstance().GetRawDataResourceForScale(
           id, ui::ScaleFactor::SCALE_FACTOR_NONE);
   return base::JSONReader::Read(manifest_contents);
 }
 
 }  // namespace android_webview