use path when serializing a package

Author: matklad

src/cargo/core/package.rs

@@ -63,7 +63,7 @@ struct SerializedPackage<'a> {
     dependencies: &'a [Dependency],
     targets: Vec<&'a Target>,
     features: &'a FeatureMap,
-    manifest_path: &'a str,
+    manifest_path: &'a Path,
     metadata: Option<&'a toml::Value>,
     authors: &'a [String],
     categories: &'a [String],
@@ -113,7 +113,7 @@ impl ser::Serialize for Package {
             dependencies: summary.dependencies(),
             targets,
             features: summary.features(),
-            manifest_path: &self.manifest_path.display().to_string(),
+            manifest_path: &self.manifest_path,
             metadata: self.manifest.custom_metadata(),
             authors,
             categories,