SOLR-17934: Remove Request ID based tracing

[epugh]

https://issues.apache.org/jira/browse/SOLR-17934

Description

Remove Request ID

Solution

I thought it would be more intrusive to remove this, seems pretty straingt forward.

[dsmiley]

Changes seem fine.

I see a test failure: org.apache.solr.client.solrj.impl.CloudSolrClientRoutingTest#routeParamHandling

  2> 	at org.apache.solr.handler.component.DebugComponent.handleResponses(DebugComponent.java:196)
  2> java.lang.NullPointerException: Cannot invoke "org.apache.solr.common.util.NamedList.get(String)" because the return value of "org.apache.solr.common.util.NamedList.get(String)" is null
  2> 	at org.apache.solr.handler.component.DebugComponent.handleResponses(DebugComponent.java:196) ~[main/:?]
  2> 	at org.apache.solr.handler.component.SearchHandler.processComponents(SearchHandler.java:657) ~

[epugh]

@dsmiley is it possible that part of the scope of this is to remove the CommonParams.TRACK property? The comment for it is value indicating an interest in debug output related to the distributed tracking, and I THINK by removing the request id, we have gutted what the TRACK had. I noticed it's not documented either in the ref guide, unlike some other values: https://solr.apache.org/guide/solr/latest/query-guide/common-query-parameters.html#debug-parameter. I can't really figure out how to get that one test to pass that is failing without providing some sort of dummy value in the track?

[epugh]

@dsmiley is it possible that part of the scope of this is to remove the CommonParams.TRACK property? The comment for it is value indicating an interest in debug output related to the distributed tracking, and I THINK by removing the request id, we have gutted what the TRACK had. I noticed it's not documented either in the ref guide, unlike some other values: https://solr.apache.org/guide/solr/latest/query-guide/common-query-parameters.html#debug-parameter. I can't really figure out how to get that one test to pass that is failing without providing some sort of dummy value in the track?

I dug more, and it looks like that is how we track various bits of data when going to various shards... Maybe the org.apache.solr.client.solrj.impl.CloudSolrClientRoutingTest#routeParamHandling is no longer needed?

[dsmiley]

Just a quick thought -- it may be helpful to go back to the commit that added this (I remember; it was Jason and I was looking at it), and see what it touched exactly. It's so long ago that a revert will unlikely be suitable but that's fine. If that doesn't readily uncover a fix to whatever is stuck here, just LMK and I'll debug.

[epugh]

@dsmiley I've poked again at this, and I would love fresh eyes on this.... Would you be willing to take a look? It's so close...