SERVER-43946 Converting BinData of type ByteArrayDeprecated from KeyString->BSON->KeyString should produce identical KeyStrings

Author: GWlodarek

src/mongo/db/storage/key_string_test.cpp

@@ -306,6 +306,10 @@ TEST_F(KeyStringBuilderTest, Simple1) {
         }                                                                  \
     } while (0)
 
+TEST_F(KeyStringBuilderTest, DeprecatedBinData) {
+    ROUNDTRIP(version, BSON("" << BSONBinData(nullptr, 0, ByteArrayDeprecated)));
+}
+
 TEST_F(KeyStringBuilderTest, ActualBytesDouble) {
     // just one test like this for utter sanity