Gfx: Make AccurateText=0 more consistent with GDI+ for D2D
The height is now based on a formula that should be exactly equal to that provided by GDI+. The padding should now be equal on the left and right sides now. There may be some discrepancies in overall width, but it should always be reasonably to close to GDI+.

In addition, this makes D2D behavior match GDI+ when a newline character is the last character of the text.
Gfx: Make AccurateText=1 more consistent with GDI+ for D2D when a newline character is the last character of the text