UCB: RepoContent::RepoContent use OUString::startsWith instead copy.
UCB: RepoContent::RepoContent use OUString::startsWith instead copy.

Change-Id: Ib504585572ae9bada60076828ade8197331d5fda
Reviewed-on: https://gerrit.libreoffice.org/6463
Reviewed-by: Caolán McNamara <301f5784f9f6aac04077f24f1e5abc31af69d401@redhat.com>
Tested-by: Caolán McNamara <301f5784f9f6aac04077f24f1e5abc31af69d401@redhat.com>

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