fix unittest

My previous commit did change the stroke of the testing brush
used for performance measurement. The color differences are below
3 levels of 256 which is not visible by the naked eye :-)

diff --git a/tests/correct_docPaint_flat.png b/tests/correct_docPaint_flat.png
index deaa596..e67a8ad 100644 (file)
Binary files a/tests/correct_docPaint_flat.png and b/tests/correct_docPaint_flat.png differ