test: Match gccgo error messages.
test: Match gccgo error messages.

explicit.go:36:4: error: incompatible types in assignment (need explicit conversion)
explicit.go:41:4: error: incompatible types in assignment (type has no methods)
explicit.go:42:4: error: incompatible types in assignment (need explicit conversion)
explicit.go:45:5: error: incompatible types in assignment (need explicit conversion; missing method ?N?)
explicit.go:48:9: error: invalid type conversion (need explicit conversion; missing method ?N?)
explicit.go:51:4: error: incompatible types in assignment
explicit.go:51:7: error: invalid type conversion (need explicit conversion)
explicit.go:57:10: error: impossible type assertion: type does not implement interface (type has no methods)
explicit.go:62:10: error: impossible type assertion: type does not implement interface (incompatible type for method ?M? (different number of parameters))
explicit.go:67:5: error: incompatible type in initialization (type has no methods)
explicit.go:68:5: error: incompatible type in initialization (incompatible type for method ?M? (different number of parameters))
explicit.go:70:11: error: invalid type conversion (type has no methods)
explicit.go:71:11: error: invalid type conversion (incompatible type for method ?M? (different number of parameters))

R=rsc
CC=golang-dev
http://codereview.appspot.com/2139044

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