- gofmt-ify walk.go - fixed several bugs
- gofmt-ify walk.go
- fixed several bugs

R=rsc
http://go/go-review/1015015

ssrl/go,dsriram/golang,bdwalton/debian-golang,gnanderson/go,ssrl/go,tv42/old-go,tianon/debian-golang,dsriram/golang,nightlyone/golang,bdwalton/debian-golang,tianon/debian-golang,h8liu/golang,nightlyone/golang,gnanderson/go,nightlyone/golang,tv42/old-go,ssrl/go,tv42/old-go,h8liu/golang,nightlyone/golang,h8liu/golang,pombredanne/go-deleteme,tianon/debian-golang,dsriram/golang,dsriram/golang,bdwalton/debian-golang,bdwalton/debian-golang,bdwalton/debian-golang,pombredanne/go-deleteme,tianon/debian-golang,dsriram/golang,tianon/debian-golang,apparentlymart/golang,gnanderson/go,ssrl/go,tianon/debian-golang,bdwalton/debian-golang,tianon/debian-golang,gnanderson/go,pombredanne/go-deleteme,tv42/old-go,ssrl/go,apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,bdwalton/debian-golang,pombredanne/go-deleteme,pombredanne/go-deleteme,gnanderson/go,tv42/old-go,tv42/old-go,bdwalton/debian-golang,gnanderson/go,h8liu/golang,ssrl/go,ssrl/go,pombredanne/go-deleteme,dsriram/golang,h8liu/golang,nightlyone/golang,apparentlymart/golang,nightlyone/golang,apparentlymart/golang,nightlyone/golang,apparentlymart/golang,apparentlymart/golang,dsriram/golang,apparentlymart/golang,tianon/debian-golang,gnanderson/go,h8liu/golang,h8liu/golang