Use CallFnAfter instead of CallOnConditionKeep (#3841)

* Use CallFnAfter instead of CallOnConditionKeep

* fix periodic for callonconditionkeep

Author: ritvikrao

tests/charm++/periodic/periodic.C

@@ -34,7 +34,11 @@ class main : public CBase_main {
     delete msg;
 
     mProxy = thisProxy;
+    #ifdef CALL_FN_AFTER
     startTime = CkWallTimer();
+    #else
+    startTime = 0.0;
+    #endif
     gProxy = CProxy_testGroup::ckNew(COUNTER_MAX);
     CkPrintf("Testing Converse periodic callbacks on %d PEs for %d seconds\n",
              CkNumPes(), COUNTER_MAX);