update http_accept_language and try to find the preferred locale first, should fix #2715

Gemfile

@@ -91,7 +91,7 @@ gem 'acts-as-taggable-on', :git => 'git://github.com/diaspora/acts-as-taggable-o
 # URIs and HTTP
 
 gem 'addressable', '2.2.4', :require => 'addressable/uri'
-gem 'http_accept_language', :git => 'git://github.com/iain/http_accept_language.git', :ref => '0b78aa7849fc90cf9e12'
+gem 'http_accept_language', '~> 1.0.2'
 gem 'typhoeus'
 
 # views

Gemfile.lock

@@ -31,13 +31,6 @@ GIT
       oauth2 (= 0.5.0)
       sinatra
 
-GIT
-  remote: git://github.com/iain/http_accept_language.git
-  revision: 0b78aa7849fc90cf9e12586af162fa4c408a795d
-  ref: 0b78aa7849fc90cf9e12
-  specs:
-    http_accept_language (1.0.1)
-
 GEM
   remote: http://rubygems.org/
   specs:
@@ -194,6 +187,7 @@ GEM
       heroku (>= 2)
       rails (>= 2)
     highline (1.6.9)
+    http_accept_language (1.0.2)
     i18n (0.5.0)
     i18n-inflector (2.6.3)
       i18n (>= 0.4.1)
@@ -443,7 +437,7 @@ DEPENDENCIES
   haml
   heroku
   heroku_san
-  http_accept_language!
+  http_accept_language (~> 1.0.2)
   i18n-inflector-rails (~> 1.0)
   jammit (= 0.6.5)
   jasmine (~> 1.1.2)

app/controllers/application_controller.rb

@@ -76,7 +76,9 @@ class ApplicationController < ActionController::Base
     if user_signed_in?
       I18n.locale = current_user.language
     else
-      I18n.locale = request.compatible_language_from AVAILABLE_LANGUAGE_CODES
+      locale = request.preferred_language_from AVAILABLE_LANGUAGE_CODES
+      locale ||= request.compatible_language_from AVAILABLE_LANGUAGE_CODES
+      I18n.locale = locale
     end
   end