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pkg/front_end/lib/src/fasta/source/source_library_builder.dart

Index: pkg/front_end/lib/src/fasta/source/source_library_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
index 8786b0270e032961f4f1cd5a92832e321dd20d82..7b76ddaee92c6a82e173f45ce48a9d31aac09609 100644
--- a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
@@ -87,6 +87,8 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
 
   bool get isPart => partOfName != null || partOfUri != null;
 
+  bool get isPatch;
+
   List<T> get types => libraryDeclaration.types;
 
   T addNamedType(String name, List<T> arguments, int charOffset);
@@ -148,7 +150,7 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
       resolvedUri = uri.resolve(path);
       newFileUri = fileUri.resolve(path);
     }
-    parts.add(loader.read(resolvedUri, newFileUri));
+    parts.add(loader.read(resolvedUri, fileUri: newFileUri));
   }
 
   void addPartOf(List<MetadataBuilder> metadata, String name, String uri) {