Add reusePort argument to ServerSocket.

runtime/bin/socket_patch.dart

Index: runtime/bin/socket_patch.dart
diff --git a/runtime/bin/socket_patch.dart b/runtime/bin/socket_patch.dart
index 4fffbf7681da5b896221836d310aa03aa98cb514..5083e280e701209375fbd24df09ea9a37784cec7 100644
--- a/runtime/bin/socket_patch.dart
+++ b/runtime/bin/socket_patch.dart
@@ -6,8 +6,9 @@ patch class RawServerSocket {
   /* patch */ static Future<RawServerSocket> bind(address,
                                                   int port,
                                                   {int backlog: 0,
-                                                   bool v6Only: false}) {
-    return _RawServerSocket.bind(address, port, backlog, v6Only);
+                                                   bool v6Only: false,
+                                                   bool reusePort: false}) {
+    return _RawServerSocket.bind(address, port, backlog, v6Only, reusePort);
   }
 }
 
@@ -319,7 +320,8 @@ class _NativeSocket extends NativeFieldWrapperClass1 {
   static Future<_NativeSocket> bind(host,
                                     int port,
                                     int backlog,
-                                    bool v6Only) {
+                                    bool v6Only,
+                                    bool reusePort) {
     return new Future.value(host)
         .then((host) {
           if (host is _InternetAddress) return host;
@@ -337,7 +339,8 @@ class _NativeSocket extends NativeFieldWrapperClass1 {
           var result = socket.nativeCreateBindListen(address._sockaddr_storage,
                                                      port,
                                                      backlog,
-                                                     v6Only);
+                                                     v6Only,
+                                                     reusePort);
           if (result is OSError) {
             throw new SocketException("Failed to create server socket",
                                       osError: result,
@@ -655,7 +658,8 @@ class _NativeSocket extends NativeFieldWrapperClass1 {
       native "Socket_WriteList";
   nativeCreateConnect(List<int> addr,
                       int port) native "Socket_CreateConnect";
-  nativeCreateBindListen(List<int> addr, int port, int backlog, bool v6Only)
+  nativeCreateBindListen(
+      List<int> addr, int port, int backlog, bool v6Only, bool reusePort)
       native "ServerSocket_CreateBindListen";
   nativeAccept(_NativeSocket socket) native "ServerSocket_Accept";
   int nativeGetPort() native "Socket_GetPort";
@@ -673,11 +677,12 @@ class _RawServerSocket extends Stream<RawSocket>
   static Future<_RawServerSocket> bind(address,
                                        int port,
                                        int backlog,
-                                       bool v6Only) {
+                                       bool v6Only,
+                                       bool reusePort) {
     if (port < 0 || port > 0xFFFF)
       throw new ArgumentError("Invalid port $port");
     if (backlog < 0) throw new ArgumentError("Invalid backlog $backlog");
-    return _NativeSocket.bind(address, port, backlog, v6Only)
+    return _NativeSocket.bind(address, port, backlog, v6Only, reusePort)
         .then((socket) => new _RawServerSocket(socket));
   }
 
@@ -893,8 +898,9 @@ patch class ServerSocket {
   /* patch */ static Future<ServerSocket> bind(address,
                                                int port,
                                                {int backlog: 0,
-                                                bool v6Only: false}) {
-    return _ServerSocket.bind(address, port, backlog, v6Only);
+                                                bool v6Only: false,
+                                                bool reusePort: false}) {
+    return _ServerSocket.bind(address, port, backlog, v6Only, reusePort);
   }
 }
 
@@ -905,8 +911,9 @@ class _ServerSocket extends Stream<Socket>
   static Future<_ServerSocket> bind(address,
                                     int port,
                                     int backlog,
-                                    bool v6Only) {
-    return _RawServerSocket.bind(address, port, backlog, v6Only)
+                                    bool v6Only,
+                                    bool reusePort) {
+    return _RawServerSocket.bind(address, port, backlog, v6Only, reusePort)
         .then((socket) => new _ServerSocket(socket));
   }