DevTools: remote debugging should work in the IPv6-only environment.

chrome/browser/devtools/remote_debugging_server.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/devtools/remote_debugging_server.h"
 
 #include <utility>
 
 #include "base/lazy_instance.h"
 #include "base/macros.h"
@@ skipping 27 matching lines @@
 
 class TCPServerSocketFactory
     : public devtools_http_handler::DevToolsHttpHandler::ServerSocketFactory {
  public:
   TCPServerSocketFactory(const std::string& address, uint16_t port)
       : address_(address),
         port_(port),
         last_tethering_port_(kMinTetheringPort) {}
 
  private:
+  scoped_ptr<net::ServerSocket> CreateLocalHostServerSocket(int port) {
+    scoped_ptr<net::ServerSocket> socket(
+        new net::TCPServerSocket(nullptr, net::NetLog::Source()));
+    if (socket->ListenWithAddressAndPort(
+            "127.0.0.1", port, kBackLog) == net::OK)
+      return socket;

[mmenke, 2016/04/01 18:41:21]

Where's the RemoteDebuggingClient?  Would it be better to just listen on both
IPv6 and IPv4?

[mmenke, 2016/04/01 18:42:16]

Also, it's possible the port could be used by another app on IPv4, but could be
free on IPv6.

+    if (socket->ListenWithAddressAndPort("::1", port, kBackLog) == net::OK)
+      return socket;
+    return scoped_ptr<net::ServerSocket>();
+  }
+
   // devtools_http_handler::DevToolsHttpHandler::ServerSocketFactory.
   scoped_ptr<net::ServerSocket> CreateForHttpServer() override {
     scoped_ptr<net::ServerSocket> socket(
         new net::TCPServerSocket(nullptr, net::NetLog::Source()));
-    if (socket->ListenWithAddressAndPort(address_, port_, kBackLog) != net::OK)
-      return scoped_ptr<net::ServerSocket>();
-
-    return socket;
+    if (address_.empty())
+      return CreateLocalHostServerSocket(port_);
+    if (socket->ListenWithAddressAndPort(address_, port_, kBackLog) == net::OK)
+      return socket;
+    return scoped_ptr<net::ServerSocket>();
   }
 
   scoped_ptr<net::ServerSocket> CreateForTethering(std::string* name) override {
     if (!g_tethering_enabled.Get())
       return scoped_ptr<net::ServerSocket>();
 
     if (last_tethering_port_ == kMaxTetheringPort)
       last_tethering_port_ = kMinTetheringPort;
     uint16_t port = ++last_tethering_port_;
     *name = base::UintToString(port);
-    scoped_ptr<net::TCPServerSocket> socket(
-        new net::TCPServerSocket(nullptr, net::NetLog::Source()));
-    if (socket->ListenWithAddressAndPort("127.0.0.1", port, kBackLog) !=
-        net::OK) {
-      return scoped_ptr<net::ServerSocket>();
-    }
-    return std::move(socket);
+    return CreateLocalHostServerSocket(port);
   }
 
   std::string address_;
   uint16_t port_;
   uint16_t last_tethering_port_;
 
   DISALLOW_COPY_AND_ASSIGN(TCPServerSocketFactory);
 };
 
 class ChromeDevToolsHttpHandlerDelegate
@@ skipping 94 matching lines @@
       debug_frontend_dir,
       version_info::GetProductNameAndVersionForUserAgent(),
       ::GetUserAgent()));
 }
 
 RemoteDebuggingServer::~RemoteDebuggingServer() {
   // Ensure Profile is alive, because the whole DevTools subsystem
   // accesses it during shutdown.
   DCHECK(g_browser_process->profile_manager());
 }