rustc-ap-serialize 351.0.0

Automatically published version of the package `serialize` in the rust-lang/rust repository from commit 51cc3cdcf060c1bf3e4d45947f7a6bc20f9960f7 The publishing script for this crate lives at: https://github.com/alexcrichton/rustc-auto-publish

Support code for encoding and decoding types.