Fix #186531: trimming margins when paperColor!=white
Review Request #125721 - Created Oct. 20, 2015 and submitted
Fix #186531: trimming margins when paperColor!=white. When paper color was changed in accessibility settings, margins are not correctly determined anymore. The attached patch was initially published in 2013 by a user named lauri-lyly.
the fix was proposed in 2013, https://bugs.launchpad.net/ubuntu/+source/okular/+bug/635026, confirmed multiple times.
Attached patch solved problem for me on Ubuntu vivid.