Start better error reporting for sockets

tests/standalone/src/io/EchoServerStreamTest.dart

Index: tests/standalone/src/io/EchoServerStreamTest.dart
diff --git a/tests/standalone/src/io/EchoServerStreamTest.dart b/tests/standalone/src/io/EchoServerStreamTest.dart
index 03d2472598500bbf33164bab1f1b4ecd62b9abe1..cb45fbb2fc445ed29e437d29575f42a2c6bfee0e 100644
--- a/tests/standalone/src/io/EchoServerStreamTest.dart
+++ b/tests/standalone/src/io/EchoServerStreamTest.dart
@@ -35,8 +35,8 @@ class EchoServerGame {
 
   void sendData() {
 
-    void errorHandler() {
-      Expect.fail("Socket error");
+    void errorHandler(Exception e) {
+      Expect.fail("Socket error $e");
     }
 
     void connectHandler() {
@@ -161,8 +161,8 @@ class EchoServer extends TestingServer {
       }
     }
 
-    void errorHandler() {
-      Expect.fail("Socket error");
+    void errorHandler(Exception e) {
+      Expect.fail("Socket error $e");
     }
 
     inputStream = connection.inputStream;