[CSS21] Missing "the" in section 9.5

In the fourth paragraph of section 9.5:
http://www.w3.org/TR/CSS21/visuren.html#floats
we should insert the word "the" (currently missing in the spec) here:

  However, line boxes created next to the float are shortened to
  make room for ***the*** margin box of the float.

-David

-- 
L. David Baron                                 http://dbaron.org/
Mozilla Corporation                       http://www.mozilla.com/