Add missing bug reference to ChangeLog.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@36720 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/WebCore/ChangeLog b/WebCore/ChangeLog
index b50c9fa..5bf874e 100644
--- a/WebCore/ChangeLog
+++ b/WebCore/ChangeLog
@@ -24,6 +24,8 @@
         Reviewed by Dan Bernstein.
 
         Fix memory leak.
+        
+        https://bugs.webkit.org/show_bug.cgi?id=20505
 
         * platform/wx/wxcode/mac/carbon/fontprops.cpp:
         (GetTextExtent):