"sql_plugin.cc, dynamic_array is not dynamic"
  When the DYNAMIC_ARRAYs were resized, pointers became invalid.
  Solved by only storing pointers within the DYNAMIC_ARRAYs.


sql/sql_plugin.cc:
  Bug27836
    Store pointers to data structures in dynamic arrays: plugin_dl_array, plugin_array
    Allocate data structures in plugin_mem_root