Adds WebWorker support to NetInfo v3.

LayoutTests/netinfo/resources/web-worker.js

Index: LayoutTests/netinfo/resources/web-worker.js
diff --git a/LayoutTests/netinfo/resources/web-worker.js b/LayoutTests/netinfo/resources/web-worker.js
new file mode 100644
index 0000000000000000000000000000000000000000..32b8bc40acb7e437ee3f1227f9682163e55144bc
--- /dev/null
+++ b/LayoutTests/netinfo/resources/web-worker.js
@@ -0,0 +1,7 @@
+addEventListener('message', function(e) {
+    self.postMessage(navigator.connection.type);
+}, false);
+
+navigator.connection.addEventListener('typechange', function() {
+    self.postMessage(navigator.connection.type);
+}, false);