image: fix build accidentally deleted one method TBR=rsc
image: fix build
accidentally deleted one method
TBR=rsc

R=rsc
CC=golang-dev
http://codereview.appspot.com/4438090

mhennings/marcohennings-go,bryanxu/go-zh,rflanagan/reginaldflanagan-project1,scirelli/scirelli-go,Triskite/willstone-goclone,npe9/noahevans-go9,webfd/go-zh,rflanagan/reginaldflanagan-project1,sanjosh/sanjos100-tipc,glycerine/jeaten-go-arrayof-structof,scirelli/scirelli-go,bryanxu/go-zh,rflanagan/reginaldflanagan-project1,bryanxu/go-zh,d0f/go-zh,d0f/go-zh,mhennings/marcohennings-go,rdp/rogerpack2005-golang,glycerine/jeaten-go-arrayof-structof,glycerine/jeaten-go-arrayof-structof,bryanxu/go-zh,npe9/noahevans-go9,rflanagan/reginaldflanagan-project1,scirelli/scirelli-go,scirelli/scirelli-go,Triskite/willstone-goclone,mhennings/marcohennings-go,bryanxu/go-zh,mhennings/marcohennings-go,bryanxu/go-zh,rdp/rogerpack2005-golang,npe9/noahevans-go9,rdp/rogerpack2005-golang,sanjosh/sanjos100-tipc,d0f/go-zh,rdp/rogerpack2005-golang,scirelli/scirelli-go,webfd/go-zh,rflanagan/reginaldflanagan-project1,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,d0f/go-zh,glycerine/jeaten-go-arrayof-structof,Triskite/willstone-goclone,d0f/go-zh,rdp/rogerpack2005-golang,scirelli/scirelli-go,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,d0f/go-zh,rflanagan/reginaldflanagan-project1,mhennings/marcohennings-go,npe9/noahevans-go9,webfd/go-zh,glycerine/jeaten-go-arrayof-structof,webfd/go-zh,npe9/noahevans-go9,webfd/go-zh,d0f/go-zh,bryanxu/go-zh,mhennings/marcohennings-go,Triskite/willstone-goclone,mhennings/marcohennings-go,Triskite/willstone-goclone,Triskite/willstone-goclone,npe9/noahevans-go9,Triskite/willstone-goclone,webfd/go-zh,glycerine/jeaten-go-arrayof-structof,sanjosh/sanjos100-tipc,webfd/go-zh,mhennings/marcohennings-go,bryanxu/go-zh,npe9/noahevans-go9,rdp/rogerpack2005-golang,sanjosh/sanjos100-tipc,rdp/rogerpack2005-golang,rflanagan/reginaldflanagan-project1,glycerine/jeaten-go-arrayof-structof,rflanagan/reginaldflanagan-project1,npe9/noahevans-go9,scirelli/scirelli-go,glycerine/jeaten-go-arrayof-structof,Triskite/willstone-goclone,d0f/go-zh,scirelli/scirelli-go,webfd/go-zh,rdp/rogerpack2005-golang