Auto merge of #2035 - Turbo87:fetch-adapter, r=locks
Auto merge of #2035 - Turbo87:fetch-adapter, r=locks

Remove obsolete `FetchAdapter` mixin

`ember-data` will use it `fetch()` automatically now (see https://github.com/emberjs/data/pull/6082)

Resolves https://github.com/rust-lang/crates.io/issues/1995

r? @locks

rust-lang/crates.io,rust-lang/crates.io,rust-lang/crates.io,rust-lang/crates.io