Comment 120 for bug 214366

IMHO:
1. while(condition) is only appropriate, if the condition is determined outside the loop.
2. define variables only in the scope, where they are used.
3. for(...) is appropriate if there is a counting variable, which is only used inside the loop
4. If you look closer, in your code snippet you could fairly use while(true) and define containsChild inside the loop.