[rust] Add explicit dependency on owning_ref 0.4.0

Change-Id: Id1a7a6ef2a1c414012eeb405fa72a92219da105f
diff --git a/rustc_deps/Cargo.lock b/rustc_deps/Cargo.lock
index 2b31921..3a57fe9 100644
--- a/rustc_deps/Cargo.lock
+++ b/rustc_deps/Cargo.lock
@@ -511,6 +511,7 @@
  "nom 3.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "num 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-bigint 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "owning_ref 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "pest 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pest_derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/rustc_deps/Cargo.toml b/rustc_deps/Cargo.toml
index 5b96f9a..00ab0d3 100644
--- a/rustc_deps/Cargo.toml
+++ b/rustc_deps/Cargo.toml
@@ -44,6 +44,7 @@
 nom = "3.2"
 num = "0.2"
 num-bigint = { version = "0.2", features = ["rand"] }
+owning_ref = "0.4.0"
 parking_lot = "0.6"
 pin-utils = "=0.1.0-alpha.4"
 pretty_assertions = "0.5.1"