SwContentArr: fix STL conversion:
SwContentArr: fix STL conversion:

It appears that the operator== for SwContent always returns false,
so 81181891c93faee024799991317ac2c451f4c0c4 changed the semantics;
use o3tl::find_partialorder_ptrequals to fix it.

Change-Id: Ib4f040f03a9eaeec9a2973f5a93a22a387232017

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