D22865: remove drawing a black line segment at the end of the plot

[Nathaniel Graham]

ngraham added reviewers: Plasma, mart.

REPOSITORY
  R296 KDeclarative

REVISION DETAIL
  https://phabricator.kde.org/D22865

To: miklosm, #plasma, mart
Cc: kde-frameworks-devel, LeGast00n, sbergeron, michaelh, ngraham, bruns