Description:
------------
When trying to execute multiple queryes with multi_query method, when first query is ok, and second one is broken, the exception is not thrown when iterating second function's resultset of the multiquery. Only ::error is set.

Reproduce code:
---------------
<?php
mysqli_report( MYSQLI_REPORT_STRICT | MYSQLI_REPORT_ERROR );

try
{
	$m = new mysqli('**', '**', '**', '**');
	$m->multi_query('select 1; bug;');
	do {

       /* store first result set */
       if ($result = $m->store_result())
       {
           while ($row = $result->fetch_row())
           {
               printf("%s\n", $row[0]);
           }
           $result->close();
       }
       /* print divider */
       if ($m->more_results()) {
           printf("-----------------\n");
       }
   }
   while ($m->next_result());
   echo $m->error;
}
catch (mysqli_sql_exception  $e)
{
	var_dump($e);
}




Expected result:
----------------
1 ----------------- You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'bug' at line 1

Actual result:
--------------
1 ----------------- 
object(mysqli_sql_exception)[2]
  protected 'message' => 'You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near &apos;bug; bug&apos; at line 1' (length=154)
  private 'string' => '' (length=0)
  protected 'code' => 1064
  protected 'file' => '**' (length=35)
  protected 'line' => 7
  private 'trace' => 
    array
      0 => 
        array
          'file' => '**' (length=35)
          'line' => 7
          'function' => 'multi_query' (length=11)
          'class' => 'mysqli' (length=6)
          'type' => '->' (length=2)
          'args' => 
            array
              0 => 'bug; bug;' (length=9)
  protected 'sqlstate' => '42000' (length=5)