[kernel] debugging for in statement

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

Index: pkg/front_end/lib/src/fasta/kernel/body_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index 65f324a8ba4f63c6f4176187e1f10a29838bc4ec..9b11214d4b1064880c15a02b58651950c8e4f2a2 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -1935,7 +1935,7 @@ class BodyBuilder extends ScopeListener<JumpTarget> implements BuilderHelper {
           "Expected lvalue, but got ${lvalue}", forToken.next.next.charOffset));
     }
     Statement result = new ForInStatement(variable, expression, body,
-        isAsync: awaitToken != null);
+        isAsync: awaitToken != null)..fileOffset = body.fileOffset;
     if (breakTarget.hasUsers) {
       result = new LabeledStatement(result);
       breakTarget.resolveBreaks(result);