Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY


innobase/dict/dict0dict.c:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY
innobase/include/dict0dict.h:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY
innobase/include/row0mysql.h:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY
sql/ha_innodb.cc:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY
sql/sql_select.cc:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY
include/my_base.h:
  Fix Bug #1942: do not retrieve all columns in a table if we only need the 'ref' of the row (usually, the PRIMARY KEY) to calculate an ORDER BY