Import Cobalt 19.master.0.203780

Includes the following patches:
  https://cobalt-review.googlesource.com/c/cobalt/+/5210
    by errong.leng@samsung.com
  https://cobalt-review.googlesource.com/c/cobalt/+/5270
    by linus.wang@samsung.com
diff --git a/src/third_party/web_platform_tests/notifications/event-onshow.html b/src/third_party/web_platform_tests/notifications/event-onshow.html
new file mode 100644
index 0000000..7cc2be9
--- /dev/null
+++ b/src/third_party/web_platform_tests/notifications/event-onshow.html
@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Notification.onshow (basic)</title>
+<link rel="author" title="Intel" href="http://www.intel.com/">
+<link rel="author" title="Xin Liu" href="mailto:xinx.liu@intel.com">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+test(function() {
+    if (Notification.permission != "granted") {
+        this.force_timeout()
+        this.set_status(this.NOTRUN, "You must allow notifications for this"
+            + " origin before running this test.")
+    } else {
+        var t = async_test("Invoked the onshow event handler.")
+        var notification = new Notification("New Email Received")
+        notification.onshow = t.step_func(function(e) {
+            assert_equals(Object.prototype.toString.call(e), "[object Event]")
+            assert_equals(e.type, "show", "Checked the event type.")
+            notification.close()
+            t.done()
+        })
+    }
+}, "Checked test prerequisites.")
+</script>