fdo#51324 lp#1017125 rhbz#806236 rhbz#823272: erase on invalid iterators
fdo#51324 lp#1017125 rhbz#806236 rhbz#823272: erase on invalid iterators

* the iterators returned by equal_range are invalidated by modification
  (which deleting them clearly is)
* possibly only a partial fix as there is more abuse of equal_range in that
  file

Change-Id: Ie9ba01e91cb449a32d77a69590bda2125f0924e1

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core