Refactorings for TranslateUri and its tests.

pkg/front_end/lib/src/base/processed_options.dart

Index: pkg/front_end/lib/src/base/processed_options.dart
diff --git a/pkg/front_end/lib/src/base/processed_options.dart b/pkg/front_end/lib/src/base/processed_options.dart
index d525d15ed294e48cb269033c4a57ef3ae2fa9fc4..c37a9f495d8d2ccfaf1bf6076ee36c48a752738c 100644
--- a/pkg/front_end/lib/src/base/processed_options.dart
+++ b/pkg/front_end/lib/src/base/processed_options.dart
@@ -221,17 +221,17 @@ class ProcessedOptions {
       await _getPackages();
       // TODO(scheglov) Load SDK libraries from whatever format we decide.
       // TODO(scheglov) Remove the field "_raw.dartLibraries".
-      var libraries = _raw.dartLibraries ?? await _parseLibraries();
+      var libraries = _raw.dartLibraries ?? await _parseDartLibraries();
       _uriTranslator =
-          new TranslateUri(_packages, libraries, const <String, List<Uri>>{});
+          new TranslateUri(libraries, const <String, List<Uri>>{}, _packages);
       ticker.logMs("Read packages file");
     }
     return _uriTranslator;
   }
 
-  Future<Map<String, Uri>> _parseLibraries() async {
+  Future<Map<String, Uri>> _parseDartLibraries() async {
     Uri librariesJson = _raw.sdkRoot?.resolve("lib/libraries.json");
-    return await computeLibraries(fileSystem, librariesJson);
+    return await computeDartLibraries(fileSystem, librariesJson);
   }
 
   /// Get the package map which maps package names to URIs.