Fixes HUDI-38: Reduce memory overhead of WriteStatus

- For implicit indexes (e.g BloomIndex), don't buffer up written records
 - By default, only collect 10% of failing records to avoid OOMs
 - Improves debuggability via above, since data errors can now show up in collect()
 - Unit tests & fixing subclasses & adjusting tests

hoodie-client/src/test/java/com/uber/hoodie/common/TestRawTripPayload.java

@@ -144,6 +144,10 @@ public class TestRawTripPayload implements HoodieRecordPayload<TestRawTripPayloa
 
     private Map<String, String> mergedMetadataMap = new HashMap<>();
 
+    public MetadataMergeWriteStatus(Boolean trackSuccessRecords, Double failureFraction) {
+      super(trackSuccessRecords, failureFraction);
+    }
+
     public static Map<String, String> mergeMetadataForWriteStatuses(List<WriteStatus> writeStatuses) {
       Map<String, String> allWriteStatusMergedMetadataMap = new HashMap<>();
       for (WriteStatus writeStatus : writeStatuses) {