default void cacheBlock(BlockCacheKey cacheKey, Cacheable buf, boolean inMemory,
    boolean waitWhenCache) {
    cacheBlock(cacheKey, buf, inMemory);
  }
Add block to cache.
@param cacheKey      The block's cache key.
@param buf           The block contents wrapped in a ByteBuffer.
@param inMemory      Whether block should be treated as in-memory
@param waitWhenCache Whether to wait for the cache to be flushed mainly when BucketCache is
                     configured.
hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/BlockCache.java