cmd/go: diagnose invalid coverage runs
cmd/go: diagnose invalid coverage runs

# bufio
coverage analysis cannot handle package (bufio_test imports testing imports bufio)
# bytes
coverage analysis cannot handle package (bytes_test imports encoding/base64 imports bytes)
# crypto/cipher
coverage analysis cannot handle package (cipher_test imports crypto/aes imports crypto/cipher)
# debug/dwarf
coverage analysis cannot handle package (dwarf_test imports debug/elf imports debug/dwarf)
# errors
coverage analysis cannot handle package (errors_test imports fmt imports errors)
# flag
coverage analysis cannot handle package (flag_test imports testing imports flag)
# fmt
coverage analysis cannot handle package (fmt_test imports testing imports fmt)
# go/ast
coverage analysis cannot handle package (ast_test imports go/format imports go/ast)
# image
coverage analysis cannot handle package (image_test imports image/gif imports image)
# io
coverage analysis cannot handle package (io_test imports bytes imports io)
# math
coverage analysis cannot handle package (math_test imports fmt imports math)
# net/http
coverage analysis cannot handle package (http_test imports net/http/httptest imports net/http)
# os
coverage analysis cannot handle package (os_test imports flag imports os)
# path/filepath
coverage analysis cannot handle package (filepath_test imports io/ioutil imports path/filepath)
# reflect
coverage analysis cannot handle package (reflect_test imports flag imports reflect)
# runtime
coverage analysis cannot handle package (runtime_test imports fmt imports runtime)
# runtime/pprof
coverage analysis cannot handle package (pprof_test imports testing imports runtime/pprof)
# sort
coverage analysis cannot handle package (sort_test imports testing imports sort)
# strconv
coverage analysis cannot handle package (strconv_test imports fmt imports strconv)
# strings
coverage analysis cannot handle package (strings_test imports testing imports strings)
# sync
coverage analysis cannot handle package (sync_test imports fmt imports sync)
# sync/atomic
coverage analysis cannot handle package (atomic_test imports testing imports sync/atomic)
# syscall
coverage analysis cannot handle package (syscall_test imports flag imports syscall)
# text/tabwriter
coverage analysis cannot handle package (tabwriter_test imports testing imports text/tabwriter)
# time
coverage analysis cannot handle package (time_test imports encoding/gob imports time)
# unicode
coverage analysis cannot handle package (unicode_test imports testing imports unicode)
# unicode/utf8
coverage analysis cannot handle package (utf8_test imports bytes imports unicode/utf8)

R=r
CC=golang-dev
https://codereview.appspot.com/10216043

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang