Bug 878935 followup - touch CLOBBER file to clean up bustage

CLOBBER

@@ -22,4 +22,4 @@
 # changes to stick? As of bug 928195, this shouldn't be necessary! Please
 # don't change CLOBBER for WebIDL changes any more.
 
-Bug 932982 apparently requires a clobber or else we get B2G mochitest-2 failures.
+Bug 878935 landed without a UUID change (and was since backed out)