TestRandomChains fail with Shingle+CommonGrams [LUCENE-4170]

ant test -Dtestcase=TestRandomChains -Dtests.method=testRandomChains -Dtests.seed=12635ABB4F789F2A -Dtests.multiplier=3 -Dtests.locale=pt -Dtests.timezone=America/Argentina/Salta -Dargs="-Dfile.encoding=ISO8859-1"

This test has two shinglefilters, then a common-grams filter. I think posLen impls in commongrams and/or shingle has a bug if the input is already a graph.


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Migrated from [LUCENE-4170](https://issues.apache.org/jira/browse/LUCENE-4170) by Robert Muir (@rmuir), 2 votes, updated May 03 2013
Attachments: [LUCENE-4170.patch](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-4170/LUCENE-4170.patch), [recursive.shinglefilter.output.png](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-4170/recursive.shinglefilter.output.png)
Linked issues:
- #4549

Start by running the supplied ant command for TestRandomChains and testRandomChains with the recorded seed. Then inspect the ShingleFilter and common-grams filter implementations, using the attached recursive.shinglefilter.output.png and LUCENE-4170.patch as context. Done means reproducing the failure, identifying the position-length issue, and making the test pass.

Written by the indexing model from the issue text.