Rewrite performed with this command:
sed -i '' 's_code.google.com/p/go\._golang.org/x/_g' \
$(grep -lr 'code.google.com/p/go.' *)
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/170920043
Fix output of packages with multiple files.
Remove extra output when filter is requested.
Fixesgolang/go#7115.
R=bradfitz, adg
CC=golang-codereviews
https://golang.org/cl/52750044