[sensors] Dispatch sensor events using postTask

third_party/WebKit/Source/modules/sensor/Sensor.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "modules/sensor/Sensor.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/dom/ExecutionContextTask.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "device/generic_sensor/public/interfaces/sensor.mojom-blink.h"
 #include "modules/sensor/SensorErrorEvent.h"
 #include "modules/sensor/SensorPollingStrategy.h"
 #include "modules/sensor/SensorProviderProxy.h"
 #include "modules/sensor/SensorReading.h"
 #include "modules/sensor/SensorReadingEvent.h"
 
 using namespace device::mojom::blink;
 
@@ skipping 242 matching lines @@
     DCHECK(m_polling);
     m_polling->stopPolling();
     return;
   }
 
   DCHECK(m_sensorProxy);
   DCHECK(m_sensorProxy->isInitialized());
   m_sensorProxy->updateInternalReading();
 
   DCHECK(m_sensorReading);
-  if (m_sensorReading->isReadingUpdated(m_storedData))
-    dispatchEvent(
-        SensorReadingEvent::create(EventTypeNames::change, m_sensorReading));
+  if (getExecutionContext() &&
+      m_sensorReading->isReadingUpdated(m_storedData)) {
+    getExecutionContext()->postTask(
+        BLINK_FROM_HERE,
+        createSameThreadTask(&Sensor::notifySensorReadingChanged,
+                             wrapWeakPersistent(this)));
+  }
 
   m_storedData = m_sensorProxy->reading();
 }
 
 void Sensor::updateState(Sensor::SensorState newState) {
   if (newState == m_state)
     return;
   m_state = newState;
-  dispatchEvent(Event::create(EventTypeNames::statechange));
+  if (getExecutionContext()) {
+    getExecutionContext()->postTask(
+        BLINK_FROM_HERE, createSameThreadTask(&Sensor::notifyStateChanged,
+                                              wrapWeakPersistent(this)));
+  }
+
   updatePollingStatus();
 }
 
 void Sensor::reportError() {
   updateState(Sensor::SensorState::ERRORED);
   // TODO(Mikhail) : Dispatch Sensor Error event.
 }
 
 void Sensor::updatePollingStatus() {
   if (!m_polling)
     return;
 
   if (m_state != Sensor::SensorState::ACTIVE ||
       page()->visibilityState() != PageVisibilityStateVisible) {
     m_polling->stopPolling();
   } else {
     m_polling->startPolling();
   }
 }
 
+void Sensor::notifySensorReadingChanged() {
+  dispatchEvent(
+      SensorReadingEvent::create(EventTypeNames::change, m_sensorReading));
+}
+
+void Sensor::notifyStateChanged() {
+  dispatchEvent(Event::create(EventTypeNames::statechange));
+}
+
 }  // namespace blink