Remove Registry arguments from Enqueuer.

tests/compiler/dart2js/type_combination_test.dart

Index: tests/compiler/dart2js/type_combination_test.dart
diff --git a/tests/compiler/dart2js/type_combination_test.dart b/tests/compiler/dart2js/type_combination_test.dart
index 5d8e18d609d46349b9572f07259236746b91daa0..2dc9f61e9c18c5fed00344735f26112fdbe1110f 100644
--- a/tests/compiler/dart2js/type_combination_test.dart
+++ b/tests/compiler/dart2js/type_combination_test.dart
@@ -735,14 +735,20 @@ void main() {
     backend.interceptorsLibrary.forEachLocalMember((element) {
       if (element.isClass) {
         element.ensureResolved(compiler);
-        compiler.enqueuer.resolution.registerInstantiatedType(
-            element.rawType, compiler.globalDependencies);
+        backend.registerInstantiatedType(
+            element.rawType,
+            compiler.enqueuer.resolution,
+            compiler.globalDependencies);
       }
     });
-    compiler.enqueuer.resolution.registerInstantiatedType(
-        compiler.coreTypes.mapType(), compiler.globalDependencies);
-    compiler.enqueuer.resolution.registerInstantiatedType(
-        compiler.coreTypes.functionType, compiler.globalDependencies);
+    backend.registerInstantiatedType(
+        compiler.coreTypes.mapType(),
+        compiler.enqueuer.resolution,
+        compiler.globalDependencies);
+    backend.registerInstantiatedType(
+        compiler.coreTypes.functionType,
+        compiler.enqueuer.resolution,
+        compiler.globalDependencies);
     compiler.world.populate();
 
     // Grab hold of a supertype for String so we can produce potential