SERVER-39323 refactor index spec validation code to make it more modularized and flexible.

- Remove a "$freelist" collection reference, which was removed with MMAPv1
- Modularize a {buildIndexes:false} check that causes a IndexAlreadyExists error to be returned
- Split IndexCatalog::removeExistingIndexes into removeExistingIndexes and removeExistingIndexesNoChecks,
  to be more explicit about the internal behavior.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/mongo/db/cloner.cpp b/src/mongo/db/cloner.cpp
index 3f49093f124..b52ef891603 100644
--- a/src/mongo/db/cloner.cpp
+++ b/src/mongo/db/cloner.cpp
@@ -394,7 +394,7 @@ void Cloner::copyIndexes(OperationContext* opCtx,
     }
 
     auto indexCatalog = collection->getIndexCatalog();
-    auto prunedIndexesToBuild = indexCatalog->removeExistingIndexes(opCtx, indexesToBuild);
+    auto prunedIndexesToBuild = indexCatalog->removeExistingIndexesNoChecks(opCtx, indexesToBuild);
     if (prunedIndexesToBuild.empty()) {
         return;
     }