Line strings such as roads, rivers are not getting rendered for map files which are in SHP format.

On loading the 1:10m natural earth dataset for roads, we get the following view.

This regression is introduced due to the changes done by the patch - https://phabricator.kde.org/D1181.
After removing the pen width check in the paintInline method, on loading the 1:10m natural earth dataset for roads, we get the following view.