[REVIEW 3-6 3-5(?)] fdo#50654: update virtual device width on modifying WB_EXTRAFIELD flag

[Ivan Timofeev]

Hi,

https://bugs.freedesktop.org/show_bug.cgi?id=50654
"Writer, Ruler: Paint issue at bottom left-ruler"

http://cgit.freedesktop.org/libreoffice/core/commit/?id=84d5e639b08a1f96b41b7b5b6af51c703b0cd620
fixes it, the commit message explains all.

And although it is maybe just a cosmetic issue, it would be great to 
have the fix in 3-6 (where everyone looks to the rulers now :) and 
possibly in 3-5(?)

Thanks,
Ivan