[horde] ActiveSync: implode(): Invalid arguments passed

[Arjen de Korte]

I'm not sure if this is just logspam (everything seems to work  
normally), but for each message received through EAS, the following is  
logged:

2018-12-29T13:37:39+01:00 WARN: horde PHP ERROR: implode(): Invalid  
arguments passed [pid 10263 on line 493 of  
"/usr/share/php7/PEAR/Horde/ActiveSync/State/Sql.php"]

This is with an up-to-date Horde installation from PEAR on PHP 7.3. I  
added a Horde::debug line to log the value of $changes and got the  
attached output.
-------------- next part --------------
2018-12-29T13:37:39+01:00 DEBUG: Variable information:
array(5) {
  ["id"]=>
  string(5) "33780"
  ["mod"]=>
  int(0)
  ["flags"]=>
  array(2) {
    ["read"]=>
    string(1) "1"
    ["flagged"]=>
    string(0) ""
  }
  ["categories"]=>
  bool(false)
  ["serverid"]=>
  string(16) "Software.OpenWrt"
}

Backtrace:
1. Horde_Rpc_ActiveSync->getResponse() /srv/www/htdocs/horde/rpc.php:160
2. Horde_ActiveSync->handleRequest() /usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php:143
3. Horde_ActiveSync_Request_Base->handle() /usr/share/php7/PEAR/Horde/ActiveSync.php:839
4. Horde_ActiveSync_Request_Sync->_handle() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Base.php:256
5. Horde_ActiveSync_Request_Sync->_parseSyncFolders() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:186
6. Horde_ActiveSync_Request_Sync->_parseSyncCommands() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:754
7. Horde_ActiveSync_Connector_Importer->importMessageChange() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:974
8. Horde_ActiveSync_State_Sql->updateState() /usr/share/php7/PEAR/Horde/ActiveSync/Connector/Importer.php:236
9. Horde::debug() /usr/share/php7/PEAR/Horde/ActiveSync/State/Sql.php:494

2018-12-29T13:37:39+01:00 DEBUG: Variable information:
array(5) {
  ["id"]=>
  string(5) "33781"
  ["mod"]=>
  int(0)
  ["flags"]=>
  array(2) {
    ["read"]=>
    string(1) "1"
    ["flagged"]=>
    string(0) ""
  }
  ["categories"]=>
  bool(false)
  ["serverid"]=>
  string(16) "Software.OpenWrt"
}

Backtrace:
1. Horde_Rpc_ActiveSync->getResponse() /srv/www/htdocs/horde/rpc.php:160
2. Horde_ActiveSync->handleRequest() /usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php:143
3. Horde_ActiveSync_Request_Base->handle() /usr/share/php7/PEAR/Horde/ActiveSync.php:839
4. Horde_ActiveSync_Request_Sync->_handle() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Base.php:256
5. Horde_ActiveSync_Request_Sync->_parseSyncFolders() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:186
6. Horde_ActiveSync_Request_Sync->_parseSyncCommands() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:754
7. Horde_ActiveSync_Connector_Importer->importMessageChange() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:974
8. Horde_ActiveSync_State_Sql->updateState() /usr/share/php7/PEAR/Horde/ActiveSync/Connector/Importer.php:236
9. Horde::debug() /usr/share/php7/PEAR/Horde/ActiveSync/State/Sql.php:494

2018-12-29T13:37:40+01:00 DEBUG: Variable information:
array(5) {
  ["id"]=>
  string(5) "33782"
  ["mod"]=>
  int(0)
  ["flags"]=>
  array(2) {
    ["read"]=>
    string(1) "1"
    ["flagged"]=>
    string(0) ""
  }
  ["categories"]=>
  bool(false)
  ["serverid"]=>
  string(16) "Software.OpenWrt"
}

Backtrace:
1. Horde_Rpc_ActiveSync->getResponse() /srv/www/htdocs/horde/rpc.php:160
2. Horde_ActiveSync->handleRequest() /usr/share/php7/PEAR/Horde/Rpc/ActiveSync.php:143
3. Horde_ActiveSync_Request_Base->handle() /usr/share/php7/PEAR/Horde/ActiveSync.php:839
4. Horde_ActiveSync_Request_Sync->_handle() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Base.php:256
5. Horde_ActiveSync_Request_Sync->_parseSyncFolders() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:186
6. Horde_ActiveSync_Request_Sync->_parseSyncCommands() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:754
7. Horde_ActiveSync_Connector_Importer->importMessageChange() /usr/share/php7/PEAR/Horde/ActiveSync/Request/Sync.php:974
8. Horde_ActiveSync_State_Sql->updateState() /usr/share/php7/PEAR/Horde/ActiveSync/Connector/Importer.php:236
9. Horde::debug() /usr/share/php7/PEAR/Horde/ActiveSync/State/Sql.php:494