Merge branch '3.4' into 4.2

* 3.4:
  Fix Twig 1.x compatibility
  [Translator] Improve farsi(persian) translations for Form
  Improve fa translations
  Added tests to cover the possibility of having scalars as services.
  fixed tests on old PHP versions
  [FrameworkBundle] Inform the user when save_path will be ignored
  fixed CS
  [Translator] Load plurals from po files properly
  [EventDispatcher] Add tag kernel.rest on 'debug.event_dispatcher' service
  [Console] Update to inherit and add licence
  [Intl] Remove --dev from intl compile autoloader
  [Intl] Init compile tmp volume
  PHP 5 compat
  Add test case
  Update Request.php
  Don't assume port 0 for X-Forwarded-Port
  Load plurals from mo files properly

Author: nicolas-grekas

Request.php

@@ -913,8 +913,8 @@ public function getPort()
             $pos = strrpos($host, ':');
         }
 
-        if (false !== $pos) {
-            return (int) substr($host, $pos + 1);
+        if (false !== $pos && $port = substr($host, $pos + 1)) {
+            return (int) $port;
         }
 
         return 'https' === $this->getScheme() ? 443 : 80;

Tests/RequestTest.php

@@ -2303,6 +2303,18 @@ public function testTrustedPort()
 
         $this->assertSame(443, $request->getPort());
     }
+
+    public function testTrustedPortDoesNotDefaultToZero()
+    {
+        Request::setTrustedProxies(['1.1.1.1'], Request::HEADER_X_FORWARDED_ALL);
+
+        $request = Request::create('/');
+        $request->server->set('REMOTE_ADDR', '1.1.1.1');
+        $request->headers->set('X-Forwarded-Host', 'test.example.com');
+        $request->headers->set('X-Forwarded-Port', '');
+
+        $this->assertSame(80, $request->getPort());
+    }
 }
 
 class RequestContentProxy extends Request