Signal no pending activity in destructed contexts.

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"
@@ skipping 114 matching lines @@
   visitor->trace(m_sensorProxy);
   ActiveScriptWrappable::trace(visitor);
   ContextLifecycleObserver::trace(visitor);
   EventTargetWithInlineData::trace(visitor);
 }
 
 bool Sensor::hasPendingActivity() const {
   if (m_state == Sensor::SensorState::Idle ||
       m_state == Sensor::SensorState::Errored)
     return false;
-  return hasEventListeners();
+  return getExecutionContext() && hasEventListeners();
 }
 
 auto Sensor::createSensorConfig() -> SensorConfigurationPtr {
   auto result = SensorConfiguration::New();
 
   double defaultFrequency = m_sensorProxy->defaultConfig()->frequency;
   double maximumFrequency = m_sensorProxy->maximumFrequency();
 
   double frequency = m_sensorOptions.hasFrequency()
                          ? m_sensorOptions.frequency()
@@ skipping 168 matching lines @@
 void Sensor::notifyOnActivate() {
   dispatchEvent(Event::create(EventTypeNames::activate));
 }
 
 void Sensor::notifyError(DOMException* error) {
   dispatchEvent(
       SensorErrorEvent::create(EventTypeNames::error, std::move(error)));
 }
 
 }  // namespace blink