Rust upgrade to rustc hash b03a2755193cd756583bcf5831cf4545d75ecb8a
Fix unit test compile error.
Fix CEF build cargo.lock file
Disable cors tests for now as they break the rust upgrade.
Rebase and fix up compile errors for rust upgrade.
auto merge of #3948 : servo/servo/rustup-20141105_2, r=jdm