Merge pull request #672 in ZP/z-push from...

Merge pull request #672 in ZP/z-push from bugfix/ZP-1379-undefined-offset-warnings-when-impersonating to develop

* commit '594690a2':
  ZP-1379 Undefined offset warnings when impersonating.

src/backend/kopano/mapiprovider.php

@@ -2805,6 +2805,9 @@ class MAPIProvider {
             if(!isset($this->storeProps[PR_IPM_OUTBOX_ENTRYID])) {
                 $this->storeProps[PR_IPM_OUTBOX_ENTRYID] = false;
             }
+            if(!isset($this->storeProps[PR_IPM_PUBLIC_FOLDERS_ENTRYID])) {
+                $this->storeProps[PR_IPM_PUBLIC_FOLDERS_ENTRYID] = false;
+            }
         }
         return $this->storeProps;
     }