gc: package paths in symbol names: don't escape periods before last slash, always escape >=0x7f.
gc: package paths in symbol names: don't escape periods before last slash, always escape >=0x7f.

R=rsc
CC=golang-dev
http://codereview.appspot.com/5323071
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go