Incorrect recersive #include detection

```
1. Have the floowing files:
common.sh:
first.sh:
    # #include "common.sh"
second.sh:
    # #include "common.sh"
result.sh:
    # #include "first.sh"
    # #include "second.sh"

2. Try to preprocess the file result.sh:
preprocess: error: detected recursive #include of 'common.sh'





```

Original issue reported on code.google.com by `bezkrova...@gmail.com` on 21 Aug 2014 at 5:39
