Pulled a significant portion of Socket implementation into BaseSocket in order to prepare for the s…

runtime/bin/socket_base_unsupported.cc

Index: runtime/bin/socket_base_unsupported.cc
diff --git a/runtime/bin/socket_unsupported.cc b/runtime/bin/socket_base_unsupported.cc
similarity index 98%
rename from runtime/bin/socket_unsupported.cc
rename to runtime/bin/socket_base_unsupported.cc
index 39b2f57e497e7fcbad606f382e4a5bde31524be9..552e625c16f6bba6ac3c2ebb51f3a4a4752bb3a5 100644
--- a/runtime/bin/socket_unsupported.cc
+++ b/runtime/bin/socket_base_unsupported.cc
@@ -39,7 +39,7 @@ void FUNCTION_NAME(Socket_CreateBindConnect)(Dart_NativeArguments args) {
 }
 
 
-void FUNCTION_NAME(Socket_IsBindError)(Dart_NativeArguments args) {
+void FUNCTION_NAME(SocketBase_IsBindError)(Dart_NativeArguments args) {
   Dart_ThrowException(
       DartUtils::NewDartArgumentError("Sockets unsupported on this platform"));
 }