auto merge of #7018 : bill-myers/rust/fix_7017, r=thestinger

Minimally fixes #7017, we were overwriting the result and thus ignoring attributes before the last.

csearch::get_item_attrs and decoder::get_item_attrs should probably also be changed to each_item_attrs using the for protocol, but that's just a minor performance/style issue.

diff --cc src/librustc/middle/ty.rs
Simple merge