Import w3c tests for the service workers

third_party/WebKit/LayoutTests/imported/wpt/service-workers/service-worker/resources/indexeddb-worker.js

+var port;
+self.addEventListener('message', function(e) {
+    var message = e.data;
+    if ('port' in message)
+      doIndexedDBTest(message.port);
+  });
+
+function doIndexedDBTest(port) {
+  var delete_request = indexedDB.deleteDatabase('db');
+  delete_request.onsuccess = function() {
+    var open_request = indexedDB.open('db');
+    open_request.onupgradeneeded = function() {
+      var db = open_request.result;
+      db.createObjectStore('store');
+    };
+    open_request.onsuccess = function() {
+      var db = open_request.result;
+      var tx = db.transaction('store', 'readwrite');
+      var store = tx.objectStore('store');
+      store.put('value', 'key');
+      tx.oncomplete = function() {
+        port.postMessage('done');
+      };
+    };
+  };
+}