[sensors] Ambient light sensor implementation for ChromeOS and Linux.

device/generic_sensor/BUILD.gn

Index: device/generic_sensor/BUILD.gn
diff --git a/device/generic_sensor/BUILD.gn b/device/generic_sensor/BUILD.gn
index 75bed031f0401f23d4c3f4c84449074e987b601c..c38df715b13ed7b54514c1fcb5c87a4fd4c74d77 100644
--- a/device/generic_sensor/BUILD.gn
+++ b/device/generic_sensor/BUILD.gn
@@ -39,6 +39,20 @@ source_set("generic_sensor") {
 
     deps += [ ":jni_headers" ]
   }
+
+  if (is_chromeos || is_linux) {
+    sources += [
+      "ambient_light_reader_iio.cc",
+      "ambient_light_reader_iio.h",
+      "platform_sensor_ambient_light_iio.cc",
+      "platform_sensor_ambient_light_iio.h",
+      "platform_sensor_provider_iio.cc",
+      "polling_platform_sensor.cc",
+      "polling_platform_sensor.h",
+    ]
+
+    sources -= [ "platform_sensor_provider_default.cc" ]
+  }
 }
 
 if (is_android) {