Bug 1424280 - Replace serde and serde_derive with Gankro's modified branch. r=jrmuizel

The branch is based off serde 1.0.23 and includes additional changes for faster
enum deserialization which we want for WebRender. The changes are in the process
of being upstreamed but will take a while.

MozReview-Commit-ID: 4xaPQpffzYL

.cargo/config.in

@@ -2,5 +2,10 @@
 registry = 'https://github.com/rust-lang/crates.io-index'
 replace-with = 'vendored-sources'
 
+[source."https://github.com/gankro/serde"]
+git = "https://github.com/gankro/serde"
+branch = "deserialize_from_enums3"
+replace-with = "vendored-sources"
+
 [source.vendored-sources]
 directory = '@top_srcdir@/third_party/rust'

toolkit/library/gtest/rust/Cargo.toml

@@ -47,3 +47,5 @@ panic = "abort"
 
 [patch.crates-io]
 libudev-sys = { path = "../../../../dom/webauthn/libudev-sys" }
+serde = { git = "https://github.com/gankro/serde", branch = "deserialize_from_enums3" }
+serde_derive = { git = "https://github.com/gankro/serde", branch = "deserialize_from_enums3", feature = "deserialize_from" }

toolkit/library/rust/Cargo.toml

@@ -48,3 +48,5 @@ panic = "abort"
 
 [patch.crates-io]
 libudev-sys = { path = "../../../dom/webauthn/libudev-sys" }
+serde = { git = "https://github.com/gankro/serde", branch = "deserialize_from_enums3" }
+serde_derive = { git = "https://github.com/gankro/serde", branch = "deserialize_from_enums3", feature = "deserialize_from" }