Temporary fix for pcbnew crashes on default canvas text edits.

[clothbot]

Just FYI, while you're poking around at pcbnew code, this is the quick-fix that stops pcbnew from crashing when you edit text fields in "default" canvas:

http://bazaar.launchpad.net/~andrew-plumb/kicad/kicad/revision/4381

Unfortunately, it also disables auto-refreshing the canvas so you have to Cmd-R to manually see changes take effect. Perhaps you can come up with a more elegant fix.

Related bug reports in the KiCad system: https://bugs.launchpad.net/kicad/+bug/1230090 https://bugs.launchpad.net/kicad/+bug/768706