account predicates that become sargable after reading const tables.
In some cases this resulted in choosing non-optimal execution plans.
Now info of such potentially saragable predicates is saved in
an array and after reading const tables we check whether this
predicates has become saragable.



mysql-test/r/select.result:
  Added a test case for bug #19579.
mysql-test/t/select.test:
  Added a test case for bug #19579.
sql/item_cmpfunc.cc:
  Fixed bug #19579: at range analysis optimizer did not take into 
  account predicates that become sargable after reading const tables.
  Added a counter of between predicates.
sql/sql_base.cc:
  Fixed bug #19579: at range analysis optimizer did not take into 
  account predicates that become sargable after reading const tables.
  Added a counter of between predicates.
sql/sql_lex.cc:
  Fixed bug #19579: at range analysis optimizer did not take into 
  account predicates that become sargable after reading const tables.
  Added a counter of between predicates.
sql/sql_lex.h:
  Fixed bug #19579: at range analysis optimizer did not take into 
  account predicates that become sargable after reading const tables.
  Added a counter of between predicates.
sql/sql_select.cc:
  Fixed bug #19579: at range analysis optimizer did not take into 
  account predicates that become sargable after reading const tables.
  Now info of such potentially saragable predicates is saved in
  an array and after reading const tables we check whether this
  predicates has become saragable.