Don't commit an empty version tag when extending calender recurrences. Fixes bug #12240.

docs/changelog/7.x.x.txt

@@ -5,6 +5,7 @@
  - fixed #12227: Corrected AssetReport such that OrderBy works correctly.
  - fixed #12238: Old template attachement in search template slows down sites
  - fixed #12239: Still get cart error message after removing extra recurring items from the cart
+ - fixed #12240: Empty Extend Calendar Recurrance version tags
 
 7.10.22
  - rfe   #12223: Add date type to content profiling (metadata)

lib/WebGUI/Workflow/Activity/ExtendCalendarRecurrences.pm

@@ -194,7 +194,13 @@ sub processRecurrence {
         $event->generateRecurrence($d);
     }
 
-    $versionTag->commit;
+    ##If nothing needed to happen, then don't keep the tag around.
+    if ($versionTag->getAssetCount > 0) {
+        $versionTag->commit;
+    }
+    else {
+        $versionTag->rollback;
+    }
     return $time_limit ? 1 : 0;
 } ## end sub processRecurrence