The current behavior is inconsistent across different configurations.
The signature is the top line for FullDocumentation, but the last line
for synopsis documentation.
Change-Id: I2fe1e1c7bfa38ae46fda06b0ecd4c7712b0e74af
GitHub-Last-Rev: d3b768558f21f518d1296b6fc776cf3974f441d9
GitHub-Pull-Request: golang/tools#241
Reviewed-on: https://go-review.googlesource.com/c/tools/+/242104
Reviewed-by: Rebecca Stambler <rstambler@golang.org>