[kernel] debugging for in statement

pkg/kernel/lib/binary/ast_from_binary.dart

Index: pkg/kernel/lib/binary/ast_from_binary.dart
diff --git a/pkg/kernel/lib/binary/ast_from_binary.dart b/pkg/kernel/lib/binary/ast_from_binary.dart
index aa9641b672f5901a4a675b1089cd4fb6f5e31dbc..b867b61b35cefa2182d766ee8e374c9fa683ed78 100644
--- a/pkg/kernel/lib/binary/ast_from_binary.dart
+++ b/pkg/kernel/lib/binary/ast_from_binary.dart
@@ -894,11 +894,13 @@ class BinaryBuilder {
       case Tag.AsyncForInStatement:
         bool isAsync = tag == Tag.AsyncForInStatement;
         int variableStackHeight = variableStack.length;
+        var offset = readOffset();
         var variable = readAndPushVariableDeclaration();
         var iterable = readExpression();
         var body = readStatement();
         variableStack.length = variableStackHeight;
-        return new ForInStatement(variable, iterable, body, isAsync: isAsync);
+        return new ForInStatement(variable, iterable, body, isAsync: isAsync)
+          ..fileOffset = offset;
       case Tag.SwitchStatement:
         var expression = readExpression();
         int count = readUInt();