[08/10] gdiplus: GdipMeasureString/GdipDrawString should add extra space around the text.

[Vincent Povirk]

> Since I have no tests for GdipMeasureCharacterRanges I don't want to break
> it inadvertently. If somebody proves that GdipMeasureCharacterRanges should
> be affected by extra padding as well, merging the code to gdip_format_string
> shouldn't be too hard.

Well, I'm saying you'll break it if you only change the other two
functions and leave this one alone. It's more important for
DrawString, MeasureString, and MeasureCharacterRanges to be consistent
with each other than with Windows. Applications won't typically rely
on specific measurements, but they WILL rely on the measurements from
MeasureCharacterRanges and MeasureString to match the actual result
from DrawString.

It should be obvious that changing the way DrawString lays out the
text, or changing the measurements of some text, without a
corresponding change in the other functions, will make the
measurements WRONG, even if they happen to pass your tests and match
the results on Windows. If you want to change the layout for only some
of the string functions, you're going to need some very strong
justification for that.