Fix test for NTLM auth over H2: HttpNetworkTransactionTest.NTLMOverHttp2

The test was simulating the H2 server hanging up after sending an H2
challenge, and then negotiating a new H1 connection, regardless of
whether net/ tried to negotiate H2 or H1 when re-establishing the
connection. This CL keeps the H2 session open, and explicitly checks
that when re-establishing a connection, we only try to negotiate H1.

Bug: 996042
Change-Id: Icb2d0e39382f9173308582b19d836a9cd26f047f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1762458
Commit-Queue: Matt Menke <mmenke@chromium.org>
Reviewed-by: Bence Béky <bnc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#689020}

net/http/http_network_transaction_unittest.cc

@@ -7573,18 +7573,9 @@ TEST_F(HttpNetworkTransactionTest, NTLMOverHttp2) {
               ntlm::test::kExpectedAuthenticateMsgEmptyChannelBindingsV2)),
       &authenticate_msg);
 
-  // Retry with authorization header.
-  spdy::SpdyHeaderBlock request_headers1(
-      spdy_util_.ConstructGetHeaderBlock(kUrl));
-  request_headers1["authorization"] = std::string("NTLM ") + negotiate_msg;
-  spdy::SpdySerializedFrame request1(spdy_util_.ConstructSpdyHeaders(
-      3, std::move(request_headers1), LOWEST, true));
-
-  spdy::SpdySerializedFrame rst(
-      spdy_util_.ConstructSpdyRstStream(3, spdy::ERROR_CODE_HTTP_1_1_REQUIRED));
-
   MockWrite writes0[] = {CreateMockWrite(request0, 0)};
-  MockRead reads0[] = {CreateMockRead(resp, 1), MockRead(ASYNC, 0, 2)};
+  MockRead reads0[] = {CreateMockRead(resp, 1),
+                       MockRead(SYNCHRONOUS, ERR_IO_PENDING, 2)};
 
   // Retry yet again using HTTP/1.1.
   MockWrite writes1[] = {
@@ -7627,7 +7618,11 @@ TEST_F(HttpNetworkTransactionTest, NTLMOverHttp2) {
 
   SSLSocketDataProvider ssl0(ASYNC, OK);
   ssl0.next_proto = kProtoHTTP2;
+  ssl0.next_protos_expected_in_ssl_config =
+      NextProtoVector{kProtoHTTP2, kProtoHTTP11};
   SSLSocketDataProvider ssl1(ASYNC, OK);
+  // When creating the second connection, only HTTP/1.1 should be allowed.
+  ssl1.next_protos_expected_in_ssl_config = NextProtoVector{kProtoHTTP11};
   session_deps_.socket_factory->AddSSLSocketDataProvider(&ssl0);
   session_deps_.socket_factory->AddSSLSocketDataProvider(&ssl1);