bug #2272 Fix unconsistent behavior with "get" and "is" (wolfx)

This PR was squashed before being merged into the 1.x branch (closes #2272).

Discussion
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Fix unconsistent behavior with "get"  and "is"

Commits
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8fb35d5 Fix unconsistent behavior with "get"  and "is"

lib/Twig/Template.php

@@ -604,6 +604,9 @@ abstract class Twig_Template implements Twig_TemplateInterface
             } else {
                 $methods = get_class_methods($object);
             }
+            // sort values to have consistent behavior, so that "get" methods win precedence over "is" methods
+            sort($methods);
+
             $cache = array();
 
             foreach ($methods as $method) {