Only return eventhandler tokens in stacks of 8, to avoid runtime calls.

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 0e7abdb4bf98b0f310f54bf90f848b97838de460..d3ccf0f57334b8665ebec4a1b109579df7d20877 100644
--- a/runtime/bin/socket_patch.dart
+++ b/runtime/bin/socket_patch.dart
@@ -410,6 +410,8 @@ class _NativeSocket extends NativeFieldWrapperClass1 {
 
   int available = 0;
 
+  int returnTokens = 0;
+
   bool sendReadEvents = false;
   bool readEventIssued = false;
 
@@ -818,8 +820,13 @@ class _NativeSocket extends NativeFieldWrapperClass1 {
         }
       }
     }
-    if (eventPort != null && !isClosing && !isClosed) {
-      sendToEventHandler(1 << RETURN_TOKEN_COMMAND);
+    if (eventPort != null && !isClosing && !isClosed && !isListening) {
+      returnTokens++;
+      if (returnTokens == 8) {
+        // Return in batches of 8.

[Søren Gjesse, 2014/03/25 13:31:22]

assert(1 << FIRST_COMMAND < returnTokens)

[Anders Johnsen, 2014/03/25 13:43:35]

Done.

+        sendToEventHandler((1 << RETURN_TOKEN_COMMAND) | returnTokens);
+        returnTokens = 0;
+      }
     }
   }