* Allocate thd->user_var_events elements on appropriate mem_root
* If several SP statements are binlogged as a single statement, collect all user var
  accesses they make (grep for StoredRoutinesBinlogging for details)


mysql-test/r/rpl_sp_effects.result:
  Testcase for BUG#12637
mysql-test/r/sp.result:
  re-enabled test case for BUG#12297
mysql-test/t/rpl_sp_effects.test:
  Testcase for BUG#12637
mysql-test/t/sp.test:
  re-enabled test case for BUG#12297
sql/item_func.cc:
  Fix for BUG#12637: Make SPs+user variables replication work:
  * Allocate thd->user_var_events elements on appropriate mem_root
  * If several SP statements are binlogged as a single statement, collect all user var
    accesses they make.
sql/log.cc:
  Fix for BUG#12637: Make SPs+user variables replication work:
  * Allocate thd->user_var_events elements on appropriate mem_root
  * If several SP statements are binlogged as a single statement, collect all user var
    accesses they make.
sql/sp_head.cc:
  Fix for BUG#12637: Make SPs+user variables replication work:
  * Allocate thd->user_var_events elements on appropriate mem_root
  * If several SP statements are binlogged as a single statement, collect all user var
    accesses they make.
sql/sp_head.h:
  Remove compiler warning.
sql/sql_class.h:
  Fix for BUG#12637: Make SPs+user variables replication work.
sql/sql_parse.cc:
  Fix for BUG#12637: Make SPs+user variables replication work.