@Override
  public void setTracing(boolean isEnabled) {
    this.isTracingEnabled = isEnabled;
  }
Estimate the RowGroup offset given the next RG offset and isLast.

@param isCompressed is the RowGroup compressed
@param isLast is this the last RowGroup
@param nextGroupOffset the offset of the next RowGroup
@param streamLength the length of the whole Stream
@param bufferSize the size of the buffer
@return
ql/src/java/org/apache/hadoop/hive/ql/io/orc/encoded/EncodedReaderImpl.java