Fix minor complaints of Marc Alff, for patch against B-g#15776.

mysql-test/t/type_blob.test:
  Drop table in case we start from a bad state.
sql/sql_yacc.yy:
  yacc/bison is left-recursive, so FIXME statement is wrong.

mysql-test/t/type_blob.test

@@ -449,6 +449,9 @@ set @@sql_mode='';
 # raise ER_TOO_BIG_DISPLAYWIDTH
 
 # BLOB and TEXT types
+--disable_warnings
+drop table if exists b15776;
+--enable_warnings
 create table b15776 (data blob(2147483647));
 drop table b15776;
 --error ER_PARSE_ERROR
@@ -570,7 +573,7 @@ explain select cast(1 as binary(4294967296));
 explain select cast(1 as decimal(-1));
 explain select cast(1 as decimal(64, 30));
 # It's not as important which errors are raised for these, since the 
-# limit is nowhere near 3**32.  We may fix these eventually to take
+# limit is nowhere near 2**32.  We may fix these eventually to take
 # 4294967295 and still reject it because it's greater than 64 or 30, 
 # but that's not a high priority and the parser needn't worry about 
 # such a weird case.

sql/sql_yacc.yy

@@ -3010,7 +3010,7 @@ udf_type:
 
 field_list:
 	  field_list_item
-	| field_list ',' field_list_item; /* FIXME:  Should this be backward? */
+	| field_list ',' field_list_item;
 
 
 field_list_item: