mysqldumpslow is broken by the more detailed slow log format

mysqldumpslow is confused by slow query log in percona-server. This results in every single query being treated individually, preventing the tool from performing aggregate analysis.

For example asking for the top 10 slow queries results in the same query being listed 10 times

# mysqldumpslow -t 10 mysql-slow.log

Reading mysql slow query log from mysql-slow.log
Count: 1 Time=0.00s (0s) Lock=0.00s (0s) Rows=0.0 (0), pressthing[pressthing]@localhost
  # Thread_id: N Schema: pressthing_production Last_errno: N Killed: N
  # Query_time: N.N Lock_time: N.N Rows_sent: N Rows_examined: N Rows_affected: N Rows_read: N
  # Bytes_sent: N Tmp_tables: N Tmp_disk_tables: N Tmp_table_sizes: N
  # InnoDB_trx_id: F82E01
  SET timestamp=N;
  SELECT * FROM `delayed_jobs` WHERE ((run_at <= 'S' AND (locked_at IS NULL OR locked_at < 'S') OR (locked_by = 'S')) AND failed_at IS NULL) ORDER BY priority DESC, run_at ASC LIMIT N

Count: 1 Time=0.00s (0s) Lock=0.00s (0s) Rows=0.0 (0), pressthing[pressthing]@localhost
  # Thread_id: N Schema: pressthing_production Last_errno: N Killed: N
  # Query_time: N.N Lock_time: N.N Rows_sent: N Rows_examined: N Rows_affected: N Rows_read: N
  # Bytes_sent: N Tmp_tables: N Tmp_disk_tables: N Tmp_table_sizes: N
  # InnoDB_trx_id: F82365
  SET timestamp=N;
  SELECT * FROM `delayed_jobs` WHERE ((run_at <= 'S' AND (locked_at IS NULL OR locked_at < 'S') OR (locked_by = 'S')) AND failed_at IS NULL) ORDER BY priority DESC, run_at ASC LIMIT N