Split TypedSelector into Selector and TypeMask.

pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart

Index: pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
diff --git a/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart b/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
index 3c735d1aeae6649b17f3e168186c96f59572605c..2b6b9d61d847fbe4d8c675223c73c3fae7a3ca56 100644
--- a/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
+++ b/pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart
@@ -8,6 +8,7 @@ import '../constants/values.dart' as values show ConstantValue;
 import '../dart_types.dart' show DartType, InterfaceType, TypeVariableType;
 import '../elements/elements.dart';
 import '../io/source_information.dart' show SourceInformation;
+import '../types/types.dart' show TypeMask;
 import '../universe/universe.dart' show Selector, SelectorKind;
 
 import 'builtin_operator.dart';
@@ -270,6 +271,7 @@ class InvokeStatic extends Expression implements Invoke {
 class InvokeMethod extends Expression implements Invoke {
   Reference<Primitive> receiver;
   Selector selector;
+  TypeMask mask;
   final List<Reference<Primitive>> arguments;
   final Reference<Continuation> continuation;
   final SourceInformation sourceInformation;
@@ -281,6 +283,7 @@ class InvokeMethod extends Expression implements Invoke {
 
   InvokeMethod(Primitive receiver,
                this.selector,
+               this.mask,
                List<Primitive> arguments,
                Continuation continuation,
                {this.sourceInformation})