Update core-text to fix nightly compile error.

servo · bors-servo · Jul 10, 2017 · Jul 10, 2017 · Jul 10, 2017 · cc5b9981de44b2c3ce49c9c7a801c07f608e76fe
commit cc5b9981de44b2c3ce49c9c7a801c07f608e76fe
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/webrender/Cargo.toml b/webrender/Cargo.toml
@@ -45,4 +45,4 @@ dwrote = "0.4"
 
 [target.'cfg(target_os = "macos")'.dependencies]
 core-graphics = "0.8.0"
-core-text = { version = "6.0", default-features = false }
+core-text = { version = "6.1", default-features = false }