Auto merge of #135 - asajeffrey:v0.50.2, r=jdm

Version bump

This is the version bump for bindgenup, PR #134 which can land once it does.

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Author: bors-servo

Cargo.toml

@@ -2,7 +2,7 @@
 name = "mozjs_sys"
 description = "System crate for the Mozilla SpiderMonkey JavaScript engine."
 repository = "https://github.com/servo/mozjs/"
-version = "0.50.1"
+version = "0.51.0"
 authors = ["Mozilla"]
 links = "mozjs"
 build = "build.rs"