Deprecate FileUriResolver and RelativeFileUriResolver in source_io.dart, replace the usages with Re…

pkg/analyzer/lib/src/generated/source.dart

Index: pkg/analyzer/lib/src/generated/source.dart
diff --git a/pkg/analyzer/lib/src/generated/source.dart b/pkg/analyzer/lib/src/generated/source.dart
index 4ba4c51a1060f86001605bdf29801a90cb7f9b0a..2ce06edd6bd078fcef5de3b2af8ef129123ae528 100644
--- a/pkg/analyzer/lib/src/generated/source.dart
+++ b/pkg/analyzer/lib/src/generated/source.dart
@@ -15,7 +15,7 @@ import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/java_io.dart' show JavaFile;
 import 'package:analyzer/src/generated/sdk.dart' show DartSdk;
 import 'package:analyzer/src/generated/source_io.dart'
-    show FileBasedSource, FileUriResolver, PackageUriResolver;
+    show FileBasedSource, PackageUriResolver;
 import 'package:analyzer/task/model.dart';
 import 'package:package_config/packages.dart';
 import 'package:path/path.dart' as pathos;