Code review comment for lp:~muktupavels/ubuntu-themes/simplify-metacity-theme

Initial HiDPI support was backported to Metacity 3.18.3, but it has at least 3 problems:

1) gradients does not scale well - there is 1px transparent line between titlebar and client window:
   https://s32.postimg.org/g5az52ukx/line.png

This is fixed in Metacity 3.18.6.

2) unfocused window middle button backgrounds does not scale well:
   https://s32.postimg.org/66q0ill5d/background.png

This merge proposal fixes problem by simply replacing image backgrounds with filled rectangles.

3) windows with odd width or height is not properly scaled because of rounding error - width and height has -1px error:
   https://s32.postimg.org/awpdvvw2t/Screenshot_from_2016_07_13_00_04_40.png

This one will not be fixed in 3.18.x.