Remove UriReferencedElement with its uri/uriOffset/uriEnd properties.

pkg/analysis_server/lib/src/services/correction/fix_internal.dart

Index: pkg/analysis_server/lib/src/services/correction/fix_internal.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index 1052c9dd0740725d1b136339385a4de8700467cb..3accd66aef277792cc2b45ff0a7fb41c4c3def71 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -1667,7 +1667,7 @@ class FixProcessor {
         // prepare library name - unit name or 'dart:name' for SDK library
         String libraryName = libraryElement.definingCompilationUnit.displayName;
         if (libraryElement.isInSdk) {
-          libraryName = imp.uri;
+          libraryName = libraryElement.source.shortName;
         }
         // don't add this library again
         alreadyImportedWithPrefix.add(libraryElement.source);