Remove Registry

pkg/compiler/lib/src/common/backend_api.dart

Index: pkg/compiler/lib/src/common/backend_api.dart
diff --git a/pkg/compiler/lib/src/common/backend_api.dart b/pkg/compiler/lib/src/common/backend_api.dart
index f58ef310df36ecf6cf8365ae3dde04baedea9c54..b61309357f7d5fdea64f113f8f64b38437cdc86a 100644
--- a/pkg/compiler/lib/src/common/backend_api.dart
+++ b/pkg/compiler/lib/src/common/backend_api.dart
@@ -33,7 +33,6 @@ import '../tree/tree.dart' show Node;
 import '../universe/world_impact.dart'
     show ImpactStrategy, WorldImpact, WorldImpactBuilder;
 import 'codegen.dart' show CodegenWorkItem;
-import 'registry.dart' show Registry;
 import 'tasks.dart' show CompilerTask;
 
 abstract class Backend extends Target {
@@ -316,9 +315,6 @@ abstract class Backend extends Target {
 
   void registerMainHasArguments(Enqueuer enqueuer) {}
 
-  void registerAsyncMarker(
-      FunctionElement element, Enqueuer enqueuer, Registry registry) {}
-
   /// Returns the location of the patch-file associated with [libraryName]
   /// resolved from [plaformConfigUri].
   ///