- Avoid full inline of mark_trx_read_write() for many functions
- Avoid somewhat expensive tests for every write/update/delete row 

sql/handler.h:
  Adde ha_start_of_new_statement() to reset internal variables as part of the code in "open_table" that resets TABLE object for the new statement
  Faster mark_trx_read_write_part()
sql/sql_base.cc:
  Don't manipulate table->file internal structs directly