Revert "Handle SendSet and NewExpression through NewResolvedVisitor."

pkg/compiler/lib/src/dart_backend/placeholder_collector.dart

Index: pkg/compiler/lib/src/dart_backend/placeholder_collector.dart
diff --git a/pkg/compiler/lib/src/dart_backend/placeholder_collector.dart b/pkg/compiler/lib/src/dart_backend/placeholder_collector.dart
index f8b5495df509510c8b2d838231db41d7f93149d4..4d47c149e2c7e47562c5a69bf5a003266288fe7e 100644
--- a/pkg/compiler/lib/src/dart_backend/placeholder_collector.dart
+++ b/pkg/compiler/lib/src/dart_backend/placeholder_collector.dart
@@ -152,12 +152,6 @@ class SendVisitor extends OldResolvedVisitor {
       }
     }
   }
-
-  @override
-  handleNewExpression(NewExpression node) => visitNode(node);
-
-  @override
-  handleSendSet(SendSet node) => visitNode(node);
 }
 
 class PlaceholderCollector extends Visitor {