Re-fix pixel grid snapping on new text style icons

Trevor tweaked the pixel grid snapping on my previous commit
but it appears that introduced some errors as well. The horizontal
lines in underline-a and strikethrough-s no longer have integer
x-coordinates, and on underline-u the whole object is offset
by (0.166, 0.166).

Bug: 47780
Change-Id: I51f2605e7d8e2bab1d641f02244d5cd24f505676
Merge "Re-fix pixel grid snapping on new text style icons"