Optimization for MDEV-10411 Providing compatibility for basic PL/SQL constructs

When processing an SP body:

CREATE PROCEDURE p1 (parameters)
AS [ declarations ]
BEGIN statements
[ EXCEPTION exceptions ]
END;

the parser generates two "jump" instructions:
- from the end of "declarations" to the beginning of EXCEPTION
- from the end of EXCEPTION to "statements"

These jumps are useless if EXCEPTION does not exist.
This patch makes sure that these two "jump" instructions are
generated only if EXCEPTION really exists.

sql/sql_lex.h

@@ -3149,7 +3149,8 @@ public:
   bool sp_block_with_exceptions_finalize_executable_section(THD *thd,
                                                   uint executable_section_ip);
   bool sp_block_with_exceptions_finalize_exceptions(THD *thd,
-                                                  uint executable_section_ip);
+                                                  uint executable_section_ip,
+                                                  uint exception_count);
   // Check if "KEY IF NOT EXISTS name" used outside of ALTER context
   bool check_add_key(DDL_options_st ddl)
   {