Implementation of null-aware operators.

pkg/compiler/lib/src/scanner/array_based_scanner.dart

Index: pkg/compiler/lib/src/scanner/array_based_scanner.dart
diff --git a/pkg/compiler/lib/src/scanner/array_based_scanner.dart b/pkg/compiler/lib/src/scanner/array_based_scanner.dart
index 9fbf7152ce07bd77539bf8441d782680d4f6ec4c..85e3a3c14799839893bd8b3907c26bfe8e0a9c40 100644
--- a/pkg/compiler/lib/src/scanner/array_based_scanner.dart
+++ b/pkg/compiler/lib/src/scanner/array_based_scanner.dart
@@ -5,8 +5,9 @@
 part of scanner;
 
 abstract class ArrayBasedScanner extends AbstractScanner {
-  ArrayBasedScanner(SourceFile file, bool includeComments)
-      : super(file, includeComments);
+  ArrayBasedScanner(SourceFile file, bool includeComments,
+                    bool enableNullAwareOperators)
+      : super(file, includeComments, enableNullAwareOperators);
 
   /**
    * The stack of open groups, e.g [: { ... ( .. :]
@@ -217,4 +218,4 @@ abstract class ArrayBasedScanner extends AbstractScanner {
       groupingStack = groupingStack.tail;
     }
   }
-}
+}