Issue #3247935 by mfb: drupal_add_html_head_link(): URL in link HTTP header should not be HTML-encoded

includes/common.inc

@@ -2965,7 +2965,7 @@ function drupal_add_html_head_link($attributes, $header = FALSE) {
 
   if ($header) {
     // Also add a HTTP header "Link:".
-    $href = '<' . check_plain($attributes['href']) . '>;';
+    $href = '<' . $attributes['href'] . '>;';
     unset($attributes['href']);
     $element['#attached']['drupal_add_http_header'][] = array('Link',  $href . drupal_http_header_attributes($attributes), TRUE);
   }

modules/simpletest/tests/common.test

@@ -3342,12 +3342,15 @@ class DrupalAddHtmlHeadLinkTest extends DrupalWebTestCase {
       '</foo?bar=baz>; rel="alternate"',
       '</foo/bar>; hreflang="nl"; rel="alternate"',
       '</foo/bar>; hreflang="de"; rel="alternate"',
+      '</foo?bar=baz&baz=false>; hreflang="en"; rel="alternate"',
     ));
     $this->assertEqual($this->drupalGetHeader('Link'), $expected_link_header);
 
     // Check that duplicate alternate URLs with different hreflangs are allowed.
     $test_link = $this->xpath('//head/link[@rel="alternate"][@href="/foo/bar"]');
     $this->assertEqual(count($test_link), 2, 'Duplicate alternate URLs are allowed.');
+    // Check that link element attributes are HTML-encoded.
+    $this->assertRaw('<link href="/foo?bar=baz&amp;baz=false" hreflang="en" rel="alternate" />');
   }
 
 }

modules/simpletest/tests/common_test.module

@@ -343,5 +343,10 @@ function common_test_html_head_link() {
     'hreflang' => 'de',
     'rel' => 'alternate',
   ), TRUE);
+  drupal_add_html_head_link(array(
+    'href' => '/foo?bar=baz&baz=false',
+    'hreflang' => 'en',
+    'rel' => 'alternate',
+  ), TRUE);
   return '';
 }