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/websockets/Secure-Send-null.htm b/src/third_party/web_platform_tests/websockets/Secure-Send-null.htm
new file mode 100644
index 0000000..1adf3c9
--- /dev/null
+++ b/src/third_party/web_platform_tests/websockets/Secure-Send-null.htm
@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>W3C WebSocket API - Send null data - Secure WebSocket</title>
+    <script type="text/javascript" src="/resources/testharness.js"></script>
+    <script type="text/javascript" src="/resources/testharnessreport.js"></script>
+    <script type="text/javascript" src="websocket.js?pipe=sub"></script>
+</head>
+<body>
+    <div id="log"></div>
+    <script type="text/javascript">
+
+        var testOpen = async_test("W3C WebSocket API - Send null data on a Secure WebSocket - Connection should be opened");
+        var testMessage = async_test("W3C WebSocket API - Send null data on a Secure WebSocket - Message should be received");
+        var testClose = async_test("W3C WebSocket API - Send null data on a Secure WebSocket - Connection should be closed");
+
+        var data = null;
+        var nullReturned = false;
+        var wsocket = CreateWebSocket(true, false, false);
+        var isOpenCalled = false;
+
+        wsocket.addEventListener('open', testOpen.step_func(function (evt) {
+            wsocket.send(data);
+            isOpenCalled = true;
+            testOpen.done();
+        }), true);
+
+        wsocket.addEventListener('message', testMessage.step_func(function (evt) {
+            if ("null" == evt.data || "" == evt.data)
+                nullReturned = true;
+            assert_true(nullReturned);
+            wsocket.close();
+            testMessage.done();
+        }), true);
+
+        wsocket.addEventListener('close', testClose.step_func(function (evt) {
+            assert_true(isOpenCalled, "WebSocket connection should be open");
+            assert_equals(evt.wasClean, true, "wasClean should be true");
+            testClose.done();
+        }), true);
+    </script>
+</body>
+</html>