Analysis
--------
For the Handler..READ statements, rows_sent and
rows_examined are always "0" in "slow_log" query tables.

The THD class has counter for rows examined and sent
for a query. But these counters are not incremented for
HANDLER...READ operations. Hence rows_sent
and rows_examined were always 0 in slow_log for
HANDLER..READ operations.

Fix:
---
Added code to increment row examined and sent counters in
HANDLER...READ statement executor.