Fix variance of BTreeMap and its companion structs.#30980

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bors merged 2 commits intorust-lang:masterfrom

gereeter:fix-btree-iter-variance

Jan 18, 2016

Commits on Jan 17, 2016

Fix and test variance of BTreeMap and its companion structs.
gereeter
committed
Expand the macro in variance-btree-invariant-types.rs to make compiletest recognize that it should error
gereeter
committed