test: a couple codegen files are not fmt'ed

[youzeliang]

go/test/codegen/bits.go

Line 347 in afe7c8d

return x&0x0000ffffffff0000

I use "fmt" code , the suggest is that return x & 0x0000ffffffff0000

[gopherbot]

Change https://golang.org/cl/268257 mentions this issue: test/codegen: go fmt

[ALTree]

Thanks for the report; you are right: that file is not gofmted. I've sent a patch.