Coordinates were mistakenly reversed for MULTIPOINT.

per-file comments:
  mysql-test/r/gis-precise.result
Fix for bug 848939 Wrong result with ST_INTERSECTION between linestrings and a polygon in 5.3-gis
        test result updated.
  mysql-test/t/gis-precise.test
Fix for bug 848939 Wrong result with ST_INTERSECTION between linestrings and a polygon in 5.3-gis
        test case added.
  sql/gcalc_tools.cc
Fix for bug 848939 Wrong result with ST_INTERSECTION between linestrings and a polygon in 5.3-gis
        coordinates set in the proper order.