ZP-968 Execute check on state usage only on ZCP versions before 7.2.3.

Nothing changes for systems without ZCP/KC as the check is executed as
before.

Released under the Affero GNU General Public License (AGPL) version 3.

src/lib/core/synccollections.php

@@ -679,11 +679,14 @@ class SyncCollections implements Iterator {
             return false;
         }
 
-        // prevent ZP-623 by checking if the states have been used before, if so force a sync on this folder
-        if (ZPush::GetDeviceManager()->CheckHearbeatStateIntegrity($spa->GetFolderId(), $spa->GetUuid(), $spa->GetUuidCounter())) {
-            ZLog::Write(LOGLEVEL_DEBUG, "SyncCollections->CountChange(): Cannot verify changes for state as it was already used. Forcing sync of folder.");
-            $this->changes[$folderid] = 1;
-            return true;
+        // Prevent ZP-623 by checking if the states have been used before, if so force a sync on this folder.
+        // ZCP/KC 7.2.3 and newer support SYNC_STATE_READONLY so this behaviour is not required (see ZP-968).
+        if (!Utils::CheckMapiExtVersion('7.2.3')) {
+            if (ZPush::GetDeviceManager()->CheckHearbeatStateIntegrity($spa->GetFolderId(), $spa->GetUuid(), $spa->GetUuidCounter())) {
+                ZLog::Write(LOGLEVEL_DEBUG, "SyncCollections->CountChange(): Cannot verify changes for state as it was already used. Forcing sync of folder.");
+                $this->changes[$folderid] = 1;
+                return true;
+            }
         }
 
         $backendFolderId = ZPush::GetDeviceManager()->GetBackendIdForFolderId($folderid);