Post-merge fixes (BUG#14498)

mysql-test/r/sp-code.result

@@ -49,7 +49,7 @@ Pos	Instruction
 9	set err@1 1
 10	hreturn 5
 11	cfetch c@0 n@4
-12	jump_if_not 15 isnull(n@4)
+12	jump_if_not 15(17) isnull(n@4)
 13	set nulls@2 (nulls@2 + 1)
 14	jump 17
 15	set count@3 (count@3 + 1)

mysql-test/t/sp.test

@@ -5230,7 +5230,9 @@ end|
 call bug14498_1()|
 call bug14498_2()|
 call bug14498_3()|
-# QQ We can't call this at the moment, due to a known bug (BUG#14643)
+# We couldn't call this before, due to a known bug (BUG#14643)
+# QQ We still can't since the new set_case_expr instruction breaks
+#    the semantics of case; it won't crash, but will get the wrong result.
 #call bug14498_4()|
 call bug14498_5()|