Add a buffer reader/writer for NTLM.

net/BUILD.gn

Index: net/BUILD.gn
diff --git a/net/BUILD.gn b/net/BUILD.gn
index 69809871e7f67a15a5ee22bc500f6fbf6d4e836e..5c5ad02d25c4e9e33beac2a95c11d2a4018463d0 100644
--- a/net/BUILD.gn
+++ b/net/BUILD.gn
@@ -1022,6 +1022,11 @@ component("net") {
       "nqe/throughput_analyzer.cc",
       "nqe/throughput_analyzer.h",
       "nqe/weighted_observation.h",
+      "ntlm/ntlm_buffer_reader.cc",
+      "ntlm/ntlm_buffer_reader.h",
+      "ntlm/ntlm_buffer_writer.cc",
+      "ntlm/ntlm_buffer_writer.h",
+      "ntlm/ntlm_constants.h",
       "proxy/dhcp_proxy_script_adapter_fetcher_win.cc",
       "proxy/dhcp_proxy_script_adapter_fetcher_win.h",
       "proxy/dhcp_proxy_script_fetcher.cc",
@@ -1763,6 +1768,16 @@ component("net") {
       }
     }
 
+    if (is_win) {
+      sources -= [
+        "ntlm/ntlm_buffer_reader.cc",
+        "ntlm/ntlm_buffer_reader.h",
+        "ntlm/ntlm_buffer_writer.cc",
+        "ntlm/ntlm_buffer_writer.h",
+        "ntlm/ntlm_constants.h",
+      ]
+    }
+
     if (!enable_built_in_dns) {
       sources -= [
         "dns/address_sorter_posix.cc",
@@ -4802,6 +4817,8 @@ test("net_unittests") {
     "nqe/observation_buffer_unittest.cc",
     "nqe/socket_watcher_unittest.cc",
     "nqe/throughput_analyzer_unittest.cc",
+    "ntlm/ntlm_buffer_reader_unittest.cc",
+    "ntlm/ntlm_buffer_writer_unittest.cc",
     "proxy/dhcp_proxy_script_adapter_fetcher_win_unittest.cc",
     "proxy/dhcp_proxy_script_fetcher_factory_unittest.cc",
     "proxy/dhcp_proxy_script_fetcher_win_unittest.cc",
@@ -5215,6 +5232,13 @@ test("net_unittests") {
     deps += [ "//gin" ]
   }
 
+  if (is_win) {
+    sources -= [
+      "ntlm/ntlm_buffer_reader_unittest.cc",
+      "ntlm/ntlm_buffer_writer_unittest.cc",
+    ]
+  }
+
   if (!use_nss_certs) {
     sources -= [
       "cert/internal/trust_store_nss_unittest.cc",