Issue #3344109 by osopolar, heddn: Add revision ID as source key to...

Issue #3344109 by osopolar, heddn: Add revision ID as source key to ContentEntity migration source (as in core)

src/Plugin/migrate/source/d8/ContentEntity.php

@@ -287,6 +287,10 @@ class ContentEntity extends SqlBase {
     $idKey = $entityDefinition->getKey('id');
     $ids[$idKey] = $this->getDefinitionFromEntity($idKey);
 
+    if (!empty($this->configuration['add_revision_id']) && $entityDefinition->isRevisionable()) {
+      $revisionKey = $entityDefinition->getKey('revision');
+      $ids[$revisionKey] = $this->getDefinitionFromEntity($revisionKey);
+    }
     if ($entityDefinition->isTranslatable()) {
       $langcodeKey = $entityDefinition->getKey('langcode');
       $ids[$langcodeKey] = $this->getDefinitionFromEntity($langcodeKey);