Add interfaces for most major Blimp net components.

blimp/net/connection_handler.h

Index: blimp/net/connection_handler.h
diff --git a/blimp/net/connection_handler.h b/blimp/net/connection_handler.h
new file mode 100644
index 0000000000000000000000000000000000000000..cfec771e295bcb26ad34d1afb351fe72b7a91946
--- /dev/null
+++ b/blimp/net/connection_handler.h
@@ -0,0 +1,20 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BLIMP_NET_CONNECTION_HANDLER_H_
+#define BLIMP_NET_CONNECTION_HANDLER_H_
+
+namespace blimp {
+
+class BlimpConnection;
+
+// Interface for objects that can take possesion of BlimpConnections.
+class ConnectionHandler {
+ public:
+  virtual void HandleConnection(scoped_ptr<BlimpConnection> connection) = 0;
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_NET_CONNECTION_HANDLER_H_