Auto merge of #3217 - alexcrichton:fix-regression, r=brson
authorbors <bors@rust-lang.org>
Wed, 26 Oct 2016 00:00:14 +0000 (17:00 -0700)
committerGitHub <noreply@github.com>
Wed, 26 Oct 2016 00:00:14 +0000 (17:00 -0700)
Ignore summaries in downloaded crates

Unfortunately historical Cargo bugs have made it such that the index sometimes
differs from the actual crate we download. Let's respect the index, however,
which should be our source of truth.

Closes #3214


Trivial merge