cgo: set alignment to 1 for unions and classes; avoids crash from divide-by-zero Fixes issue 4114.
cgo: set alignment to 1 for unions and classes; avoids crash from divide-by-zero
Fixes issue 4114.

R=golang-dev, iant, rsc, iant, devon.odell
CC=golang-dev
http://codereview.appspot.com/6553050

tv42/old-go,apparentlymart/golang,apparentlymart/golang,gnanderson/go,apparentlymart/golang,pombredanne/go-deleteme,dsriram/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,tv42/old-go,apparentlymart/golang,dsriram/golang,gnanderson/go,dsriram/golang,gnanderson/go,dsriram/golang,dsriram/golang,dsriram/golang,tv42/old-go,apparentlymart/golang,gnanderson/go,tv42/old-go,tv42/old-go,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,gnanderson/go,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,dsriram/golang,gnanderson/go,apparentlymart/golang,apparentlymart/golang,gnanderson/go