[1.3.1] Fixed bug in RemoveInvalidImg code that caused all images to be dropped

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@599 48356398-32a2-884e-a903-53898d9a118a

tests/HTMLPurifier/Strategy/RemoveForeignElementsTest.php

@@ -42,12 +42,15 @@ class HTMLPurifier_Strategy_RemoveForeignElementsTest
               ' Warning!</span>'
         );
         
-        // test removal of img tag
+        // test removal of invalid img tag
         $this->assertResult(
             '<img />',
             ''
         );
         
+        // test preservation of valid img tag
+        $this->assertResult('<img src="foobar.gif" />');
+        
     }
     
 }