[Sensors] Implement Sensor.onactivate

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 270 matching lines @@
                              wrapWeakPersistent(this)));
   }
 
   m_storedData = m_sensorProxy->sensorReading()->data();
 }
 
 void Sensor::updateState(Sensor::SensorState newState) {
   if (newState == m_state)
     return;
   m_state = newState;
-  if (getExecutionContext()) {
+  if (m_state == SensorState::ACTIVE && getExecutionContext()) {

[shalamov, 2016/11/09 11:17:16]

if (m_state == ACTIVATING && newState == ACTIVE && ...) wdyt?

I know that we set 'ACTIVATING' state in start, maybe, in case someone modifies
implementation of start you can add extra check.

     getExecutionContext()->postTask(
-        BLINK_FROM_HERE, createSameThreadTask(&Sensor::notifyStateChanged,
+        BLINK_FROM_HERE, createSameThreadTask(&Sensor::notifyOnActivate,
                                               wrapWeakPersistent(this)));
   }
 
   updatePollingStatus();
 }
 
 void Sensor::reportError(ExceptionCode code,
                          const String& sanitizedMessage,
                          const String& unsanitizedMessage) {
   updateState(Sensor::SensorState::ERRORED);
@@ skipping 16 matching lines @@
     m_polling->stopPolling();
   } else {
     m_polling->startPolling();
   }
 }
 
 void Sensor::notifySensorReadingChanged() {
   dispatchEvent(Event::create(EventTypeNames::change));
 }
 
-void Sensor::notifyStateChanged() {
-  dispatchEvent(Event::create(EventTypeNames::statechange));
+void Sensor::notifyOnActivate() {
+  dispatchEvent(Event::create(EventTypeNames::activate));
 }
 
 void Sensor::notifyError(DOMException* error) {
   dispatchEvent(
       SensorErrorEvent::create(EventTypeNames::error, std::move(error)));
 }
 
 }  // namespace blink