in default blend file
- Add new text block, enable word wrap, type in some random text.
- open 3d view so both are visible at the same time.
- In the 3d view add a circle, edit the number of sides.

now quit blender to see leak.
it seems every undo step leaks.

Error Totblock: 74
text draw cache len: 72 0x465e998
text drawcache line_height len: 12 0x4571c88
text draw cache len: 72 0x463d848
text drawcache line_height len: 4 0x46704e8
text draw cache len: 72 0x45747c8
text drawcache line_height len: 4 0x468ff08