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 d55845cc3045998093bd78a7bfde83a22e0d2beb..0707b6f6153adbb8b0d9021aeb87c60165a5ecc9 100644
--- a/net/BUILD.gn
+++ b/net/BUILD.gn
@@ -1754,6 +1754,10 @@ component("net") {
       }
     }
 
+    if (!is_win) {
+      deps += [ "//net/ntlm" ]
+    }
+
     if (!enable_built_in_dns) {
       sources -= [
         "dns/address_sorter_posix.cc",
@@ -5216,6 +5220,10 @@ test("net_unittests") {
     deps += [ "//gin" ]
   }
 
+  if (!is_win) {
+    deps += [ "//net/ntlm:ntlm_unittests" ]
+  }
+
   if (!use_nss_certs) {
     sources -= [
       "cert/internal/trust_store_nss_unittest.cc",