remove workaround for Solr bug regarding multivalued date fields

fixed in 5.4.0
http://issues.apache.org/jira/browse/SOLR-8050

source/net/yacy/search/Switchboard.java

@@ -2512,11 +2512,15 @@ public final class Switchboard extends serverSwitch {
                 // 2015-09-12 Solr v5.2.1 & v5.3
                 // this hack switches partial update off (if multivalued datefield _dts exists, like: dates_in_content_dts startDates_dts endDates_dts)
                 boolean partialUpdate = getConfigBool("postprocessing.partialUpdate", true);
+
+                /* Solr 5.4.0 bugfix see http://issues.apache.org/jira/browse/SOLR-8050 Partial update on document with multivalued date field fails
+                *
                 for (String sf : index.fulltext().getDefaultConfiguration().keySet()) {
                     if (sf.endsWith("_dts")) {
                         partialUpdate = false;
                     }
                 }
+                */
                 if (allCrawlsFinished) {
                     // refresh the search cache
                     SearchEventCache.cleanupEvents(true);

test/net/yacy/cora/federate/solr/connector/EmbeddedSolrConnectorTest.java

@@ -121,6 +121,8 @@ public class EmbeddedSolrConnectorTest {
      * Test for partial update for document containing a multivalued date field
      * this is a Solr issue (2015-09-12)
      * the test case is just to demonstrate the effect on YaCy (currently catching the solr exception and reinserting a document with fields missing)
+     *
+     * Solr 5.4.0 bugfix @see http://issues.apache.org/jira/browse/SOLR-8050 Partial update on document with multivalued date field fails
      */
     @Test
     public void testUdate_withMultivaluedDateField() throws SolrException, IOException {
@@ -142,7 +144,7 @@ public class EmbeddedSolrConnectorTest {
         fieldnames.addAll(doc.getFieldNames());
 
         SolrInputDocument sid = new SolrInputDocument();
-        sid.addField(CollectionSchema.id.name(), doc.getFieldValue(CollectionSchema.id.name()));
+        sid.addField(CollectionSchema.id.name(), id);
         sid.addField(CollectionSchema.host_s.name(), "yacy.yacy");
         solr.update(sid);
         solr.commit(true);