fdo#51954: -1 is small while STRING_NOTFOUND was great
fdo#51954: -1 is small while STRING_NOTFOUND was great

...after String -> rtl::OUString conversion in
a4cbcf2fc567393cd954d0fcc8ea0ce7d859b59f.

Change-Id: Ieb6dfce8c0cf7d8b5971d187b3b58b754c1cb02f

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