rustdoc: don't crash when an external trait's docs needs to import another trait#48415

Merged

bors merged 4 commits intorust-lang:masterfrom

QuietMisdreavus:traits-on-traits-on-traits

Feb 25, 2018

Commits on Feb 21, 2018

manually release `cx.external_traits` while building the new trait
QuietMisdreavus
committed

Commits on Feb 22, 2018