another attempt at utf-8 uploads. the last attempt broke uploads of binary files like .png
another attempt at utf-8 uploads.
the last attempt broke uploads of binary files like .png

R=r
http://go/go-review/1026025

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