[Blimp Net] Add EngineAuthHandler.

blimp/common/proto/blimp_message.proto

Index: blimp/common/proto/blimp_message.proto
diff --git a/blimp/common/proto/blimp_message.proto b/blimp/common/proto/blimp_message.proto
index 505e0f44f138852ba825d5c4fcc1ef32aa24c7fb..8584fb0e4cb5321136b8ca9ea4b9e7f4c49aa3a1 100644
--- a/blimp/common/proto/blimp_message.proto
+++ b/blimp/common/proto/blimp_message.proto
@@ -39,6 +39,7 @@ message BlimpMessage {
     RENDER_WIDGET = 3;
     INPUT = 4;
     COMPOSITOR = 5;
+    START_CONNECTION = 6;
   }
   // Identifies the feature type of this message.
   // The feature-specific contents are contained in optional fields of the same
@@ -64,5 +65,6 @@ message BlimpMessage {
   optional RenderWidgetMessage render_widget = 1002;
   optional InputMessage input = 1003;
   optional CompositorMessage compositor = 1004;
+  optional StartConnectionMessage start_connection = 1005;

[Wez, 2015/12/02 01:52:52]

Let's either move these into a general "protocol control" message namespace as
discussed offline.

[haibinlu, 2015/12/03 01:53:15]

Done.

 }