Restore original OpenSearch namespaces

Though that URL may no longer resolve, the correct XML namespace for
OpenSearch remains http://a9.com/-/spec/opensearch/1.1/ – see [1] and
[2] for some discussion clarifying this.

Similarly, the canonical namespace URL for MozSearch uses HTTP, not
HTTPS, as can be seen when visiting it (via either protocol) [3].

This reverts commit 3b86cf0.

[1]: dewitt/opensearch#3
[2]: https://groups.google.com/d/msg/opensearch/8ecuX35-lEs/JR_cs0N6k68J
[3]: https://www.mozilla.org/2006/browser/search/

Bug: T196643
Change-Id: I8d14660550a5c67cefc421a334502963bfd6ed3c

opensearch_desc.php

@@ -46,8 +46,8 @@
 print '<?xml version="1.0"?>';
 print Xml::openElement( 'OpenSearchDescription',
 	[
-		'xmlns' => 'http://www.opensearch.org/Specifications/OpenSearch/1.1',
-		'xmlns:moz' => 'https://www.mozilla.org/2006/browser/search/' ] );
+		'xmlns' => 'http://a9.com/-/spec/opensearch/1.1/',
+		'xmlns:moz' => 'http://www.mozilla.org/2006/browser/search/' ] );
 
 /* The spec says the ShortName must be no longer than 16 characters,
  * but 16 is *realllly* short. In practice, browsers don't appear to care