Using NodeFlags ctor to set InEnabledState when needed
Only run configure in the Rust submodule when we actually use it.
Merge pull request #3036 from servo/no-configure-rust-submodule

Only run configure in the Rust submodule when we actually use it.
Merge pull request #3035 from brunoabinader/fix-node-ctor

Using NodeFlags ctor to set InEnabledState when needed; r=Ms2ger
Upgrade Rust.