SynonymGraphFilter doesn't correctly consume decompounded tokens (branched token graph) [LUCENE-9173]

This is a derived issue from #10164.

When the tokenizer that is given to SynonymGraphFilter decompound tokens or emit multiple tokens at the same position, SynonymGraphFilter cannot correctly handle them (an exception will be thrown).

For example, JapaneseTokenizer (mode=SEARCH) would emit a token and two decompounded tokens for the text "株式会社":

```java
株式会社 (positionIncrement=0, positionLength=2)
株式 (positionIncrement=1, positionLength=1)
会社 (positionIncrement=1, positionLength=1)
```

Then if we give a synonym "株式会社,コーポレーション" by SynonymGraphFilterFactory (set tokenizerFactory=JapaneseTokenizerFactory) this exception is thrown.

```java
Caused by: java.lang.IllegalArgumentException: term: 株式会社 analyzed to a token (株式会社) with position increment != 1 (got: 0)
at org.apache.lucene.analysis.synonym.SynonymMap$Parser.analyze(SynonymMap.java:325) \~[lucene-analyzers-common-8.4.0.jar:8.4.0 bc02ab906445fcf4e297f4ef00ab4a54fdd72ca2 - jpountz - 2019-12-19 20:16:38]
at org.apache.lucene.analysis.synonym.SolrSynonymParser.addInternal(SolrSynonymParser.java:114) \~[lucene-analyzers-common-8.4.0.jar:8.4.0 bc02ab906445fcf4e297f4ef00ab4a54fdd72ca2 - jpountz - 2019-12-19 20:16:38]
at org.apache.lucene.analysis.synonym.SolrSynonymParser.parse(SolrSynonymParser.java:70) \~[lucene-analyzers-common-8.4.0.jar:8.4.0 bc02ab906445fcf4e297f4ef00ab4a54fdd72ca2 - jpountz - 2019-12-19 20:16:38]
at org.apache.lucene.analysis.synonym.SynonymGraphFilterFactory.loadSynonyms(SynonymGraphFilterFactory.java:179) \~[lucene-analyzers-common-8.4.0.jar:8.4.0 bc02ab906445fcf4e297f4ef00ab4a54fdd72ca2 - jpountz - 2019-12-19 20:16:38]
at org.apache.lucene.analysis.synonym.SynonymGraphFilterFactory.inform(SynonymGraphFilterFactory.java:154) \~[lucene-analyzers-common-8.4.0.jar:8.4.0 bc02ab906445fcf4e297f4ef00ab4a54fdd72ca2 - jpountz - 2019-12-19 20:16:38]
```

This isn't only limited to JapaneseTokenizer but a more general issue about handling branched token graph (decompounded tokens in the midstream).

---
Migrated from [LUCENE-9173](https://issues.apache.org/jira/browse/LUCENE-9173) by Tomoko Uchida (@mocobeta), updated Jan 27 2020
Linked issues:
- #10164

Start with SynonymGraphFilter and the failure path through SynonymMap.java, SolrSynonymParser.java, and SynonymGraphFilterFactory.java. Reproduce the exception using JapaneseTokenizer in SEARCH mode with the shown 株式会社 tokens and synonym, then inspect the linked issue #10164 for context. Done means branched or decompounded token graphs are consumed without the reported exception.

Written by the indexing model from the issue text.