Merge pull request #48 from w3c/use_initialize_operation

Use newly introduced "initialize a sensor object" operation

Author: anssiko

index.bs

@@ -33,12 +33,14 @@ urlPrefix: https://w3c.github.io/sensors; spec: GENERIC-SENSOR
     text: reporting mode; url: reporting-modes
     text: auto 
     text: construct a sensor object; url: construct-sensor-object
+    text: initialize a sensor object; url: initialize-a-sensor-object
     text: limit maximum sampling frequency; url: limit-max-frequency
     text: reduce accuracy; url: reduce-accuracy
     text: mitigation strategies; url: mitigation-strategies
     text: sampling frequency
     text: sensor type
     text: sensor readings
+    text: check sensor policy-controlled features; url: check-sensor-policy-controlled-features
 </pre>
 <pre class=biblio>
 {
@@ -230,15 +232,37 @@ The AmbientLightSensor Interface {#ambient-light-sensor-interface}
   };
 </pre>
 
-To <dfn>Construct an AmbientLightSensor Object</dfn> the user agent must invoke the 
-<a>construct a Sensor object</a> abstract operation.
+To construct an {{AmbientLightSensor}} object the user agent must invoke the
+[=construct an ambient light sensor object=] abstract operation.
 
 ### The illuminance attribute ### {#ambient-light-sensor-reading-attribute}
 
 The <a attribute for="AmbientLightSensor">illuminance</a> attribute of the {{AmbientLightSensor}}
 interface represents the [=current light level=] and returns the result of invoking
 [=get value from latest reading=] with `this` and "illuminance" as arguments.
 
+Abstract Operations {#abstract-operations}
+===================
+
+<h3 dfn export>Construct an ambient light sensor object</h3>
+
+<div algorithm="construct an ambient light sensor object">
+
+    : input
+    :: |options|, a {{SensorOptions}} object.
+    : output
+    :: An {{AmbientLightSensor}} object.
+
+    1.  Let |allowed| be the result of invoking [=check sensor policy-controlled features=]
+        with {{AmbientLightSensor}}.
+    1.  If |allowed| is false, then:
+        1.  [=Throw=] a {{SecurityError}} {{DOMException}}.
+    1.  Let |ambient_light_sensor| be the new {{AmbientLightSensor}} object.
+    1.  Invoke [=initialize a sensor object=] with |ambient_light_sensor| and |options|.
+    1.  Return |ambient_light_sensor|.
+</div>
+
+
 Use Cases and Requirements {#usecases-requirements}
 =========