bugfix: SET_TIMESTAMP log entry should have block_length and nr_page field set to avoid interfere with the readBlock/getNumberOfBytes logic.
bugfix: SET_TIMESTAMP log entry should have block_length and nr_page field set to avoid interfere with the readBlock/getNumberOfBytes logic.

songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs,songweijia/hdfsrs