[Sensors] Implement sensor data polling

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 070b3b88aa3107e7257ddbff65b4110899b8bd19..a93c3818b149ce3885b637e3dab3b674ae5a8b09 100644
--- a/third_party/WebKit/Source/modules/sensor/Sensor.cpp
+++ b/third_party/WebKit/Source/modules/sensor/Sensor.cpp
@@ -179,6 +179,15 @@ void Sensor::onStopRequestCompleted(bool result)
 void Sensor::pageVisibilityChanged()
 {
     updatePollingStatus();
+
+    if (!m_sensorProxy || !m_sensorProxy->isInitialized())
+        return;
+
+    if (page()->visibilityState() != PageVisibilityStateVisible) {
+        m_sensorProxy->suspend();
+    } else {
+        m_sensorProxy->resume();
+    }
 }
 
 void Sensor::startListening()