cursorMark ClassCastException (or incorrect results) when combined with QueryElevationComponent

When cursorMark pagination is used together with elevateIds, an exception is thrown.

Steps to reproduce described below.

1. Start solr with the `demo` core

docker run --name solr_cursor_elevate -d -p 8983:8983 solr:7.2 solr-demo

2. Add some test documents

curl http://localhost:8983/solr/demo/update?commit=true -d '
[
{{ {"id" : "book1",}}
{{ "title_t" : "book one"}}
{{ },}}
{{ {"id" : "book2",}}
{{ "title_t" : "book two"}}
{{ },}}
{{ {"id" : "book3",}}
{{ "title_t" : "book three"}}
{{ }}}
]'

3. Execute a query with cursorMark and elevateIds

curl 'http://localhost:8983/solr/demo/elevate?cursorMark=*&elevateIds=book3&enableElevation=true&df=title_t&fl=id,title_t&forceElevation=true&q=book&rows=2&sort=id%20asc'

Observe the stacktrace:
null:java.lang.ClassCastException: java.lang.Integer cannot be cast to org.apache.lucene.util.BytesRef
at org.apache.solr.schema.FieldType.marshalStringSortValue(FieldType.java:1127)
at org.apache.solr.schema.StrField.marshalSortValue(StrField.java:100)
at org.apache.solr.search.CursorMark.getSerializedTotem(CursorMark.java:250)
at org.apache.solr.handler.component.QueryComponent.doProcessUngroupedSearch(QueryComponent.java:1445)
at org.apache.solr.handler.component.QueryComponent.process(QueryComponent.java:375)
at org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:295)
at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:177)
at org.apache.solr.core.SolrCore.execute(SolrCore.java:2503)
at org.apache.solr.servlet.HttpSolrCall.execute(HttpSolrCall.java:710)
at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:516)
at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:382)
at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:326)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1751)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:582)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1180)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:512)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1112)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:213)
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:119)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
at org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:335)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
at org.eclipse.jetty.server.Server.handle(Server.java:534)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:320)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:283)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:108)
at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148)
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671)
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589)
at java.lang.Thread.run(Thread.java:748)