public synchronized void triggerCacheRefreshForTesting() {
    try {
      refreshCache();
    } catch (IOException e) {
      LOG.warn("Failed to refresh snapshot hfile cache!", e);
    }
    LOG.debug("Current cache:" + cache);
  }
Trigger a cache refresh, even if its before the next cache refresh. Does not affect pending
cache refreshes.
<p/>
Blocks until the cache is refreshed.
<p/>
Exposed for TESTING.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/snapshot/SnapshotFileCache.java