Update GeolocationController to call startUpdating() / stopUpdating() only if needed

Source/modules/geolocation/GeolocationController.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 18 matching lines @@
 #include "core/inspector/InspectorInstrumentation.h"
 #include "modules/geolocation/GeolocationClient.h"
 #include "modules/geolocation/GeolocationError.h"
 #include "modules/geolocation/GeolocationPosition.h"
 
 namespace WebCore {
 
 GeolocationController::GeolocationController(Page* page, GeolocationClient* client)
     : PageLifecycleObserver(page)
     , m_client(client)
+    , m_isClientUpdating(false)
 {
 }
 
+void GeolocationController::startUpdatingIfNeeded()
+{
+    if (m_isClientUpdating)
+        return;
+    m_isClientUpdating = true;
+    m_client->startUpdating();
+}
+
+void GeolocationController::stopUpdatingIfNeeded()
+{
+    if (!m_isClientUpdating)
+        return;
+    m_isClientUpdating = false;
+    m_client->stopUpdating();
+}
+
 GeolocationController::~GeolocationController()
 {
     ASSERT(m_observers.isEmpty());
 
     if (m_client)
         m_client->geolocationDestroyed();
 }
 
 PassOwnPtr<GeolocationController> GeolocationController::create(Page* page, GeolocationClient* client)
 {
     return adoptPtr(new GeolocationController(page, client));
 }
 
 void GeolocationController::addObserver(Geolocation* observer, bool enableHighAccuracy)
 {
     // This may be called multiple times with the same observer, though removeObserver()
     // is called only once with each.
     bool wasEmpty = m_observers.isEmpty();
     m_observers.add(observer);
     if (enableHighAccuracy)
         m_highAccuracyObservers.add(observer);
 
     if (m_client) {
         if (enableHighAccuracy)
             m_client->setEnableHighAccuracy(true);
         if (wasEmpty && page() && page()->visibilityState() == PageVisibilityStateVisible)
-            m_client->startUpdating();
+            startUpdatingIfNeeded();
     }
 }
 
 void GeolocationController::removeObserver(Geolocation* observer)
 {
     if (!m_observers.contains(observer))
         return;
 
     m_observers.remove(observer);
     m_highAccuracyObservers.remove(observer);
 
     if (m_client) {
         if (m_observers.isEmpty())
-            m_client->stopUpdating();
+            stopUpdatingIfNeeded();
         else if (m_highAccuracyObservers.isEmpty())
             m_client->setEnableHighAccuracy(false);
     }
 }
 
 void GeolocationController::requestPermission(Geolocation* geolocation)
 {
     if (m_client)
         m_client->requestPermission(geolocation);
 }
@@ skipping 36 matching lines @@
 
     return m_client->lastPosition();
 }
 
 void GeolocationController::pageVisibilityChanged()
 {
     if (m_observers.isEmpty() || !m_client)
         return;
 
     if (page() && page()->visibilityState() == PageVisibilityStateVisible)
-        m_client->startUpdating();
+        startUpdatingIfNeeded();
     else
-        m_client->stopUpdating();
+        stopUpdatingIfNeeded();
 }
 
 const char* GeolocationController::supplementName()
 {
     return "GeolocationController";
 }
 
 void provideGeolocationTo(Page* page, GeolocationClient* client)
 {
     Supplement<Page>::provideTo(page, GeolocationController::supplementName(), GeolocationController::create(page, client));
 }
 
 } // namespace WebCore