Merge branch '2.1' into 2.2

* 2.1:
  #7106 - fix for ZTS builds
  Added '@@' escaping strategy for YamlFileLoader and YamlDumper
  [Yaml] fixed bugs with folded scalar parsing
  [Form] made DefaultCsrfProvider using session_status() when available
  Added unit tests to Dumper
  Update .travis.yml (closes #7355)
  [HttpFoudantion] fixed Request::getPreferredLanguage()
  Revert "merged branch jfsimon/issue-6928 (PR #7378)"
  Routing issue with installation in a sub-directory ref: symfony/symfony#7129

Conflicts:
	.travis.yml
	src/Symfony/Bundle/FrameworkBundle/Routing/Router.php
	src/Symfony/Component/Routing/RouteCollection.php

Author: fabpot

Request.php

@@ -1345,7 +1345,18 @@ public function getPreferredLanguage(array $locales = null)
             return $locales[0];
         }
 
-        $preferredLanguages = array_values(array_intersect($preferredLanguages, $locales));
+        $extendedPreferredLanguages = array();
+        foreach ($preferredLanguages as $language) {
+            $extendedPreferredLanguages[] = $language;
+            if (false !== $position = strpos($language, '_')) {
+                $superLanguage = substr($language, 0, $position);
+                if (!in_array($superLanguage, $preferredLanguages)) {
+                    $extendedPreferredLanguages[] = $superLanguage;
+                }
+            }
+        }
+
+        $preferredLanguages = array_values(array_intersect($extendedPreferredLanguages, $locales));
 
         return isset($preferredLanguages[0]) ? $preferredLanguages[0] : $locales[0];
     }
@@ -1379,21 +1390,14 @@ public function getLanguages()
                     for ($i = 0, $max = count($codes); $i < $max; $i++) {
                         if ($i == 0) {
                             $lang = strtolower($codes[0]);
-                            // First segment of compound language codes
-                            // is added to supported languages list
-                            if (!in_array($lang, $this->languages)) {
-                                $this->languages[] = $lang;
-                            }
                         } else {
                             $lang .= '_'.strtoupper($codes[$i]);
                         }
                     }
                 }
             }
 
-            if (!in_array($lang, $this->languages)) {
-                $this->languages[] = $lang;
-            }
+            $this->languages[] = $lang;
         }
 
         return $this->languages;

Tests/RequestTest.php

@@ -1013,6 +1013,14 @@ public function testGetPreferredLanguage()
         $request = new Request();
         $request->headers->set('Accept-language', 'zh, en-us; q=0.8, en; q=0.6');
         $this->assertEquals('en', $request->getPreferredLanguage(array('fr', 'en')));
+
+        $request = new Request();
+        $request->headers->set('Accept-language', 'zh, en-us; q=0.8');
+        $this->assertEquals('en', $request->getPreferredLanguage(array('fr', 'en')));
+
+        $request = new Request();
+        $request->headers->set('Accept-language', 'zh, en-us; q=0.8, fr-fr; q=0.6, fr; q=0.5');
+        $this->assertEquals('en', $request->getPreferredLanguage(array('fr', 'en')));
     }
 
     public function testIsXmlHttpRequest()
@@ -1083,8 +1091,8 @@ public function testGetLanguages()
 
         $request = new Request();
         $request->headers->set('Accept-language', 'zh, en-us; q=0.8, en; q=0.6');
-        $this->assertEquals(array('zh', 'en', 'en_US'), $request->getLanguages());
-        $this->assertEquals(array('zh', 'en', 'en_US'), $request->getLanguages());
+        $this->assertEquals(array('zh', 'en_US', 'en'), $request->getLanguages());
+        $this->assertEquals(array('zh', 'en_US', 'en'), $request->getLanguages());
 
         $request = new Request();
         $request->headers->set('Accept-language', 'zh, en-us; q=0.6, en; q=0.8');
@@ -1101,10 +1109,6 @@ public function testGetLanguages()
         $request = new Request();
         $request->headers->set('Accept-language', 'zh, i-cherokee; q=0.6');
         $this->assertEquals(array('zh', 'cherokee'), $request->getLanguages());
-
-        $request = new Request();
-        $request->headers->set('Accept-language', 'en-us');
-        $this->assertEquals(array('en', 'en_US'), $request->getLanguages());
     }
 
     public function testGetRequestFormat()