Fix width/height inversion in dviread debug helper.

`python -mmatplotlib.dviread` is useful to verify how matplotlib parses
dvi constructs, but the output inverted the width and height of boxes.

Author: anntzer

lib/matplotlib/dviread.py

@@ -1148,6 +1148,6 @@ def _fontfile(cls, suffix, texname):
                           else ".",
                           text.width, sep="\t")
             if page.boxes:
-                print("x", "y", "w", "h", "", "(boxes)", sep="\t")
-                for x, y, w, h in page.boxes:
-                    print(x, y, w, h, sep="\t")
+                print("x", "y", "h", "w", "", "(boxes)", sep="\t")
+                for box in page.boxes:
+                    print(box.x, box.y, box.height, box.width, sep="\t")