[IndexedDB] Add Observer Tests

third_party/WebKit/LayoutTests/storage/indexeddb/resources/observer-helpers.js

+if (this.importScripts) {
+  importScripts('testharness-helpers.js');
+  importScripts('observer-actions.js');
+}
+
+window=this;
+var isWorker = window.document === undefined;
+
+// This runs two tests with the given body function, one where the database
+// changes happen in the same frame, and another where the changes happen in
+// a separate worker.
+function indexeddb_observers_test(body_func, description) {
+  var db1_prefix = 'db' + self.location.pathname + '-' + description + '1';
+  var db2_prefix = 'db' + self.location.pathname + '-' + description + '2';
+
+  var createDatabases = function(t, db1_name, db2_name, done_callback) {
+    var done_barrier = create_barrier(done_callback);
+    delete_then_open(t, db1_name, function(t, db) {
+      var os1 = db.createObjectStore('store1');
+      var os2 = db.createObjectStore('store2');
+      os1.put('b', 'a');
+      os2.put('y', 'x');
+    }, done_barrier(t));
+
+    delete_then_open(t, db2_name, function(t, db) {
+      var os1 = db.createObjectStore('store3');
+      var os2 = db.createObjectStore('store4');
+      os1.put('c', 'c');
+      os2.put('w', 'w');
+    }, done_barrier(t));
+  }
+
+  async_test(function(t) {
+    var db1_name = db1_prefix + "-frame";
+    var db2_name = db2_prefix + "-frame";
+
+    var observers_added_callback = t.step_func(function() {
+      indexeddb_observers_actions(
+          db1_name, db2_name,
+          t.unreached_func('Error performing observer actions in frame'));
+    });
+    var start_tests = t.step_func(function() {
+      body_func(t, db1_name, db2_name, observers_added_callback);
+    });
+    createDatabases(t, db1_name, db2_name, start_tests);
+  }, description + " (changes in frame).", { timeout: 20000 });
+
+  async_test(function(t) {
+    var db1_name = db1_prefix + "-worker";
+    var db2_name = db2_prefix + "-worker";
+
+    var observers_added_callback = t.step_func(function() {
+      var name_dict = {
+        db1_name: db1_name,
+        db2_name: db2_name
+      };
+      var hash_string = encodeURIComponent(JSON.stringify(name_dict));
+      var url = 'resources/observer-actions.js#' + hash_string;
+
+      // Since Chrome doesn't support starting workers in workers, we have to
+      // implement this postMessage protocol to ask our host frame to start the
+      // given worker.
+      if (isWorker) {
+        postMessage({'start_worker_url': url});
+      } else {
+        new Worker(url);
+      }
+    });
+
+    var start_tests = t.step_func(function() {
+      body_func(t, db1_name, db2_name, observers_added_callback);
+    });
+    createDatabases(t, db1_name, db2_name, start_tests);
+  }, description + ' (changes in worker).', { timeout: 20000 });
+}