Use microsecond_interval_timer() instead of my_time() in replicaiton

- Use microsecond_interval_timer() to calculate time for applying row events.
  (Faster execution)
- Removed return value for set_row_stmt_start_timestamp()
  as it was never used.

sql/log_event.cc

@@ -12963,13 +12963,13 @@ void issue_long_find_row_warning(Log_event_type type,
   if ((global_system_variables.log_warnings > 1 && 
        !rgi->is_long_find_row_note_printed()))
   {
-    time_t now= my_time(0);
-    time_t stmt_ts= rgi->get_row_stmt_start_timestamp();
+    ulonglong now= microsecond_interval_timer();
+    ulonglong stmt_ts= rgi->get_row_stmt_start_timestamp();
 
     DBUG_EXECUTE_IF("inject_long_find_row_note", 
-                    stmt_ts-=(LONG_FIND_ROW_THRESHOLD*2););
+                    stmt_ts-=(LONG_FIND_ROW_THRESHOLD*2*HRTIME_RESOLUTION););
 
-    long delta= (long) (now - stmt_ts);
+    longlong delta= (now - stmt_ts)/HRTIME_RESOLUTION;
 
     if (delta > LONG_FIND_ROW_THRESHOLD)
     {
@@ -13375,7 +13375,6 @@ int
 Delete_rows_log_event::do_after_row_operations(const Slave_reporting_capability *const, 
                                                int error)
 {
-  /*error= ToDo:find out what this should really be, this triggers close_scan in nbd, returning error?*/
   m_table->file->ha_index_or_rnd_end();
   my_free(m_key);
   m_key= NULL;

sql/rpl_rli.h

@@ -744,7 +744,7 @@ struct rpl_group_info
     Runtime state for printing a note when slave is taking
     too long while processing a row event.
    */
-  time_t row_stmt_start_timestamp;
+  longlong row_stmt_start_timestamp;
   bool long_find_row_note_printed;
   /* Needs room for "Gtid D-S-N\x00". */
   char gtid_info_buf[5+10+1+10+1+20+1];
@@ -890,17 +890,15 @@ struct rpl_group_info
   char *gtid_info();
   void unmark_start_commit();
 
-  time_t get_row_stmt_start_timestamp()
+  longlong get_row_stmt_start_timestamp()
   {
     return row_stmt_start_timestamp;
   }
 
-  time_t set_row_stmt_start_timestamp()
+  void set_row_stmt_start_timestamp()
   {
     if (row_stmt_start_timestamp == 0)
-      row_stmt_start_timestamp= my_time(0);
-
-    return row_stmt_start_timestamp;
+      row_stmt_start_timestamp= microsecond_interval_timer();
   }
 
   void reset_row_stmt_start_timestamp()