Copy all fields of NullCheck

pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart

Index: pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
diff --git a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
index eaa24e961fdbd4483df98ecb56327d46c23e950c..8f51f82d8bbd98200f190ed10c813ca9139486d0 100644
--- a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
+++ b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
@@ -995,11 +995,12 @@ class NullCheck extends Statement {
   Expression condition;
   Expression value;
   Selector selector;
+  bool useSelector;
   Statement next;
   SourceInformation sourceInformation;
 
-  NullCheck({this.condition, this.value, this.selector, this.next,
-      this.sourceInformation});
+  NullCheck({this.condition, this.value, this.selector, this.useSelector,
+      this.next, this.sourceInformation});
 
   accept(StatementVisitor visitor) {
     return visitor.visitNullCheck(this);