wlan: No longer call csrNeighborRoamHandleEmptyScanResult().

Modify csrNeighborRoamScanRequestCallback() to no longer call
csrNeighborRoamHandleEmptyScanResult() - when no roam candidates are
found during a BG scan. Instead schedule BG scans based only upon
gNeighborRoamScanRefreshPeriod. This should help prevent excessive
scanning from interfering with heartbeat monitoring.

Change-Id: Icdf0042547a1652c9635056c2b4aa017fe1372b0
CR-Fixed: 407719
diff --git a/CORE/SME/src/csr/csrNeighborRoam.c b/CORE/SME/src/csr/csrNeighborRoam.c
index e089c48..8354210 100644
--- a/CORE/SME/src/csr/csrNeighborRoam.c
+++ b/CORE/SME/src/csr/csrNeighborRoam.c
@@ -1322,11 +1322,21 @@
                 }
                 else
                 {
-                    NEIGHBOR_ROAM_DEBUG(pMac, LOGE, FL("No candidate found after scanning in state %d.. "), pNeighborRoamInfo->neighborRoamState);
-                    /* Handle it appropriately */
-                    csrNeighborRoamHandleEmptyScanResult(pMac);
+                    /* Restart the timer even in the event that we didn't obtain any candidates. */
+                    /* (We used to reset the lookup threshold, in this event.  No longer.) */
+                    hstatus = palTimerStart(pMac->hHdd, pNeighborRoamInfo->neighborScanTimer, 
+                                pNeighborRoamInfo->cfgParams.neighborScanPeriod * PAL_TIMER_TO_MS_UNIT, 
+                                eANI_BOOLEAN_FALSE);
+    
+                    if (eHAL_STATUS_SUCCESS != hstatus)
+                    {
+                        /* Timer start failed.. Should we ASSERT here??? */
+                        smsLog(pMac, LOGE, FL("Neighbor scan PAL Timer start failed, status = %d, Ignoring state transition"), status);
+                        return eHAL_STATUS_FAILURE;
+                    }
                 }
                 break;
+
 #ifdef WLAN_FEATURE_VOWIFI_11R                
             case eCSR_NEIGHBOR_ROAM_STATE_REPORT_SCAN:
                 if (!tempVal)