auto merge of #10289 : nikomatsakis/rust/issue-10157-TypeContents-refactor, r=pcwalton

See #10157. This compiles now.

Fixes #10278.

Fixed xfail for nbody shootout benchmark by correcting command line parse.
Cleaned up unneeded imports and type changes to resolve compiler warnings.
Merge branch 'master' of github.com:willingc/rust