Added a net::BidirectionalStream to expose a bidirectional streaming interface

net/BUILD.gn

Index: net/BUILD.gn
diff --git a/net/BUILD.gn b/net/BUILD.gn
index 7403fe2a68de1550f33ec7d126d2a2d62af58d8b..0b4a1137d89afbec656b5ed478ba8ced4dd0380d 100644
--- a/net/BUILD.gn
+++ b/net/BUILD.gn
@@ -46,6 +46,7 @@ disable_ftp_support = is_ios
 declare_args() {
   # Disables support for file URLs.  File URL support requires use of icu.
   disable_file_support = false
+  enable_bidirectional_stream = false
 }
 
 config("net_config") {
@@ -59,6 +60,9 @@ config("net_config") {
   if (disable_ftp_support) {
     defines += [ "DISABLE_FTP_SUPPORT=1" ]
   }
+  if (enable_bidirectional_stream) {
+    defines += [ "ENABLE_BIDIRECTIONAL_STREAM=1" ]
+  }
 }
 
 # net_internal_config is shared with net and net_small.
@@ -423,6 +427,10 @@ component("net") {
       sources += gypi_values.net_ftp_support_sources
     }
 
+    if (enable_bidirectional_stream) {
+      sources += gypi_values.net_bidirectional_stream_sources
+    }
+
     if (enable_websockets) {
       sources += gypi_values.net_websockets_sources
     }
@@ -1524,6 +1532,9 @@ test("net_unittests") {
     ]
   }
 
+  if (!enable_bidirectional_stream) {
+    sources -= [ "http/bidirectional_stream_unittest.cc" ]
+  }
   if (!enable_built_in_dns) {
     sources -= [
       "dns/address_sorter_posix_unittest.cc",