Revert the fix of Bug#38996 Race condition in ANALYZE TABLE

This is branches/zip@r6032 in SVN and _is part_ of
revid:svn-v4:16c675df-0fcb-4bc9-8058-dcc011a37293:branches/zip:6113
in BZR.

This is being reverted because now the code is serialized directly on
index->stat_n_diff_key_vals[] as the fix for
Bug#53046 dict_update_statistics_low can still be run concurrently on same table
goes.

storage/innodb_plugin/handler/ha_innodb.cc

@@ -108,7 +108,6 @@ static ulong commit_threads = 0;
 static pthread_mutex_t commit_threads_m;
 static pthread_cond_t commit_cond;
 static pthread_mutex_t commit_cond_m;
-static pthread_mutex_t analyze_mutex;
 static bool innodb_inited = 0;
 
 #define INSIDE_HA_INNOBASE_CC
@@ -2237,7 +2236,6 @@ innobase_change_buffering_inited_ok:
 	pthread_mutex_init(&prepare_commit_mutex, MY_MUTEX_INIT_FAST);
 	pthread_mutex_init(&commit_threads_m, MY_MUTEX_INIT_FAST);
 	pthread_mutex_init(&commit_cond_m, MY_MUTEX_INIT_FAST);
-	pthread_mutex_init(&analyze_mutex, MY_MUTEX_INIT_FAST);
 	pthread_cond_init(&commit_cond, NULL);
 	innodb_inited= 1;
 #ifdef MYSQL_DYNAMIC_PLUGIN
@@ -2292,7 +2290,6 @@ innobase_end(
 		pthread_mutex_destroy(&prepare_commit_mutex);
 		pthread_mutex_destroy(&commit_threads_m);
 		pthread_mutex_destroy(&commit_cond_m);
-		pthread_mutex_destroy(&analyze_mutex);
 		pthread_cond_destroy(&commit_cond);
 	}
 
@@ -7663,15 +7660,9 @@ ha_innobase::analyze(
 	THD*		thd,		/*!< in: connection thread handle */
 	HA_CHECK_OPT*	check_opt)	/*!< in: currently ignored */
 {
-	/* Serialize ANALYZE TABLE inside InnoDB, see
-	Bug#38996 Race condition in ANALYZE TABLE */
-	pthread_mutex_lock(&analyze_mutex);
-
 	/* Simply call ::info() with all the flags */
 	info(HA_STATUS_TIME | HA_STATUS_CONST | HA_STATUS_VARIABLE);
 
-	pthread_mutex_unlock(&analyze_mutex);
-
 	return(0);
 }