Add support for superSend to the new IR and dart backend.

sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart

Index: sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart b/sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart
index 3928a3b838ebd2648da0b64941fac0372ab8daf3..df9d608a91962fb859f2409cf8e40b57659381bb 100644
--- a/sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart
+++ b/sdk/lib/_internal/compiler/implementation/ir/ir_tracer.dart
@@ -167,6 +167,11 @@ class IRTracer extends TracerUtil implements ir.Visitor {
     printStmt(dummy, "This");
   }
 
+  visitSuper(ir.Super node) {
+    String dummy = names.name(node);
+    printStmt(dummy, "Super");
+  }
+
   visitInvokeContinuation(ir.InvokeContinuation node) {
     String dummy = names.name(node);
     String kont = formatReference(node.continuation);