Debugger: use correct position for for-next expression statement.

test/mjsunit/es6/regress/regress-468661.js

Index: test/mjsunit/es6/regress/regress-468661.js
diff --git a/test/mjsunit/es6/regress/regress-468661.js b/test/mjsunit/es6/regress/regress-468661.js
index e569474d23225495e78a8bf38dbd639ec39c1ee2..543a87c1df5344ee9cd9ffa4bfd93e54c6c2c02b 100644
--- a/test/mjsunit/es6/regress/regress-468661.js
+++ b/test/mjsunit/es6/regress/regress-468661.js
@@ -63,8 +63,8 @@ var sum = 0;
   debugger; // Break 0.
 
   for (let i=0; // Break 1.
-       i < 1;   // Break 2. // Break 5. // Break 6.
-       i++) {
+       i < 1;   // Break 2.  // Break 6.
+       i++) {   // Break 5.
     let key = i; // Break 3.
     sum += key;   // Break 4.
   }