Fix weird offset on 1px lines 407405

We use DDA algorythm on 1px strokes. this removes the DDA usage on this case. According to dmitry this is not done for speed reasons. And on line stroke testings this does not alter the expected 1px line the 1px preset line. However it helps in.

• Create perfect pixel lines
• Create really circular lines

Other posible solutions is to refactor the DDA algorithm as it could be wrong (havent tested in deep). However before refactoring I open this for review as it is. since it may or may no t be necessary to handle an specifyc case. (git blame could not fine the commit that introduced this 1px case)

Test Plan

(Tell us how to test the changes you made.)

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