Make the event-handler handle backpreasure.

runtime/bin/eventhandler_win.cc

Index: runtime/bin/eventhandler_win.cc
diff --git a/runtime/bin/eventhandler_win.cc b/runtime/bin/eventhandler_win.cc
index 534f3284e2e4648195d71dffafd6eb42e8c184d6..772b27e988a52784be9778769b0c3f875bf3baf1 100644
--- a/runtime/bin/eventhandler_win.cc
+++ b/runtime/bin/eventhandler_win.cc
@@ -373,9 +373,7 @@ bool DirectoryWatchHandle::IssueRead() {
   // we create it.
   if (pending_read_ != NULL) return true;
   OverlappedBuffer* buffer = OverlappedBuffer::AllocateReadBuffer(kBufferSize);
-
   ASSERT(completion_port_ != INVALID_HANDLE_VALUE);
-
   BOOL ok = ReadDirectoryChangesW(handle_,
                                   buffer->GetBufferStart(),
                                   buffer->GetBufferSize(),
@@ -1203,9 +1201,9 @@ int64_t EventHandlerImplementation::GetTimeout() {
 }
 
 
-void EventHandlerImplementation::Notify(intptr_t id,
-                                        Dart_Port dart_port,
-                                        int64_t data) {
+void EventHandlerImplementation::SendData(intptr_t id,
+                                          Dart_Port dart_port,
+                                          int64_t data) {
   InterruptMessage* msg = new InterruptMessage;
   msg->id = id;
   msg->dart_port = dart_port;
@@ -1289,7 +1287,7 @@ void EventHandlerImplementation::Start(EventHandler* handler) {
 
 
 void EventHandlerImplementation::Shutdown() {
-  Notify(kShutdownId, 0, 0);
+  SendData(kShutdownId, 0, 0);
 }
 
 }  // namespace bin