Bug 389321 - Part 3.1: Disable a problematic reftest until bug 607548 gets resolved; r=roc a=blocking-betaN+

layout/reftests/bugs/reftest.list

@@ -1353,7 +1353,9 @@ asserts(1) == 496032-1.html 496032-1-ref.html # bug 399262
 == 503364-1a.html 503364-1-ref.html
 == 503364-1b.html 503364-1-ref.html
 == 503399.html 503399-ref.html
-== 503531-1.html 503531-1-ref.html
+# Reftest for bug 503531 marked as failing; should be re-enabled when
+# bug 607548 gets resolved.
+fails == 503531-1.html 503531-1-ref.html
 == 504032-1.html 504032-1-ref.html
 == 505743-1.html about:blank
 == 506481-1.html 506481-1-ref.html