[Blimp Net] Add EngineAuthHandler.

blimp/common/proto/blimp_message.proto

 // 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.
 //
 // Contains the BlimpMessage proto which frames all messages sent over Blimp
 // subchannels. BlimpMessage protos are serialized and transmitted over the
 // wire to the Blimplet server.
 //
 // Each BlimpMessage has a few identifying fields which provide the browser
 // session and tab ID as context. The message details are stored in a
@@ skipping 10 matching lines @@
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 import "control.proto";
 import "compositor.proto";
 import "input.proto";
 import "navigation.proto";
 import "render_widget.proto";
+import "protocol_control.proto";
 
 package blimp;
 
 message BlimpMessage {
   enum Type {
     UNKNOWN = 0;
     CONTROL = 1;
     NAVIGATION = 2;
     RENDER_WIDGET = 3;
     INPUT = 4;
     COMPOSITOR = 5;
+    PROTOCOL_CONTROL = 6;
   }
 
   // Sequence number of this message, used for message acknowledgement.
   // The sender may omit this value if it is exactly one higher than the
   // message that was previously sent.
   optional int64 message_id = 1;
 
   // Identifies the feature type of this message.
   // The feature-specific contents are contained in optional fields of the same
   // name (example: use |compositor| field for type=COMPOSITOR.)
@@ skipping 11 matching lines @@
   optional int32 target_tab_id = 4;
 
   // Feature-specific messages follow.
   // Only one of these fields may be set per BlimpMessage.
   // TODO(kmarshall): use a 'oneof' union when it's supported in Chromium.
   optional ControlMessage control = 1000;
   optional NavigationMessage navigation = 1001;
   optional RenderWidgetMessage render_widget = 1002;
   optional InputMessage input = 1003;
   optional CompositorMessage compositor = 1004;
+  optional ProtocolControlMessage protocol_control = 1005;
 }