Implementation and fixes for Blimp client/engine E2E communication.

blimp/net/browser_connection_handler.cc

Index: blimp/net/browser_connection_handler.cc
diff --git a/blimp/net/browser_connection_handler.cc b/blimp/net/browser_connection_handler.cc
index 896803c68323180cf413aca9219955b3eed2eded..6a7b47428d68c5d31d8a9ff7846bbd8301605c94 100644
--- a/blimp/net/browser_connection_handler.cc
+++ b/blimp/net/browser_connection_handler.cc
@@ -42,31 +42,33 @@ scoped_ptr<BlimpMessageProcessor> BrowserConnectionHandler::RegisterFeature(
 
 void BrowserConnectionHandler::HandleConnection(
     scoped_ptr<BlimpConnection> connection) {
-  // Since there is only a single Client, assume a newer connection should
-  // replace an existing one.
-  DropCurrentConnection();
+  DCHECK(connection);
+  VLOG(1) << "HandleConnection " << connection;
+
+  if (connection_) {
+    DropCurrentConnection();
+  }
   connection_ = std::move(connection);
-  connection_->SetConnectionErrorObserver(this);
 
-  // Connect the incoming & outgoing message streams.
-  connection_->SetIncomingMessageProcessor(checkpointer_.get());
+  // Hook up message streams to the connection.
+  connection_->SetIncomingMessageProcessor(demultiplexer_.get());
   output_buffer_->SetOutputProcessor(
       connection_->GetOutgoingMessageProcessor());
+  connection_->AddConnectionErrorObserver(this);
 }
 
-void BrowserConnectionHandler::DropCurrentConnection() {
-  if (!connection_)
-    return;
+void BrowserConnectionHandler::OnConnectionError(int error) {
+  DropCurrentConnection();
+}
 
-  connection_->SetConnectionErrorObserver(nullptr);
-  connection_->SetIncomingMessageProcessor(nullptr);
+void BrowserConnectionHandler::DropCurrentConnection() {
+  DCHECK(connection_);
   output_buffer_->SetOutputProcessor(nullptr);
-  connection_.reset();
-}
 
-void BrowserConnectionHandler::OnConnectionError(int error) {
-  LOG(WARNING) << "Connection error " << net::ErrorToString(error);
-  DropCurrentConnection();
+  // Squelch any errors that are thrown as a result of dropping the connection.
+  connection_->ClearConnectionErrorObservers();
+
+  connection_.reset();
 }
 
 }  // namespace blimp