Fix for issues 3729 and 3523

compiler/java/com/google/dart/compiler/ast/DartArrayAccess.java

Index: compiler/java/com/google/dart/compiler/ast/DartArrayAccess.java
===================================================================
--- compiler/java/com/google/dart/compiler/ast/DartArrayAccess.java	(revision 9267)
+++ compiler/java/com/google/dart/compiler/ast/DartArrayAccess.java	(working copy)
@@ -13,11 +13,17 @@
 public class DartArrayAccess extends DartExpression {
 
   private DartExpression target;
+  private boolean isCascade;
   private DartExpression key;
   private MethodNodeElement element;
 
   public DartArrayAccess(DartExpression target, DartExpression key) {
+    this(target, false, key);
+  }
+
+  public DartArrayAccess(DartExpression target, boolean isCascade, DartExpression key) {
     this.target = becomeParentOf(target);
+    this.isCascade = isCascade;
     this.key = becomeParentOf(key);
   }
 
@@ -26,6 +32,10 @@
     return true;
   }
 
+  public boolean isCascade() {
+    return isCascade;
+  }
+
   public DartExpression getKey() {
     return key;
   }