[sensors] Dispatch sensor events using postTask

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

Index: third_party/WebKit/Source/modules/sensor/Sensor.cpp
diff --git a/third_party/WebKit/Source/modules/sensor/Sensor.cpp b/third_party/WebKit/Source/modules/sensor/Sensor.cpp
index 0ccfb6fe73e8c97fd04f3cb7beedccd0014c5b0a..a87b8be19f01c7b23dd3bab04323acdaa27be36c 100644
--- a/third_party/WebKit/Source/modules/sensor/Sensor.cpp
+++ b/third_party/WebKit/Source/modules/sensor/Sensor.cpp
@@ -6,6 +6,7 @@
 
 #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"
@@ -268,9 +269,13 @@ void Sensor::pollForData() {
   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();
 }
@@ -279,7 +284,12 @@ 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();
 }
 
@@ -300,4 +310,13 @@ void Sensor::updatePollingStatus() {
   }
 }
 
+void Sensor::notifySensorReadingChanged() {
+  dispatchEvent(
+      SensorReadingEvent::create(EventTypeNames::change, m_sensorReading));
+}
+
+void Sensor::notifyStateChanged() {
+  dispatchEvent(Event::create(EventTypeNames::statechange));
+}
+
 }  // namespace blink