Make the override warnings prettier.

sdk/lib/_internal/pub/lib/src/source/path.dart

Index: sdk/lib/_internal/pub/lib/src/source/path.dart
diff --git a/sdk/lib/_internal/pub/lib/src/source/path.dart b/sdk/lib/_internal/pub/lib/src/source/path.dart
index af752d674308146e3c0417f5957fafb1b77940b4..76892e1e6528a26573858f4073dff48b9382476a 100644
--- a/sdk/lib/_internal/pub/lib/src/source/path.dart
+++ b/sdk/lib/_internal/pub/lib/src/source/path.dart
@@ -113,6 +113,16 @@ class PathSource extends Source {
     return description;
   }
 
+  /// Converts a parsed relative path to its original relative form.
+  String formatDescription(String containingPath, description) {
+    var sourcePath = description["path"];
+    if (description["relative"]) {
+      sourcePath = path.relative(description['path'], from: containingPath);
+    }
+
+    return sourcePath;
+  }
+
   /// Ensures that [description] is a valid path description and returns a
   /// normalized path to the package.
   ///