[Blimp Net] Add EngineAuthHandler.

blimp/common/proto/start_connection.proto

Index: blimp/common/proto/start_connection.proto
diff --git a/blimp/common/proto/size.proto b/blimp/common/proto/start_connection.proto
similarity index 51%
copy from blimp/common/proto/size.proto
copy to blimp/common/proto/start_connection.proto
index f6ba801495df51dbe000a44b4369861105d1ba3d..c8ddce3e25426c1cbbe7811bf8f6c4b0799754db 100644
--- a/blimp/common/proto/size.proto
+++ b/blimp/common/proto/start_connection.proto
@@ -8,10 +8,9 @@ option optimize_for = LITE_RUNTIME;
 
 package blimp;
 
-// Contains display information that represents resize events coming from the
-// client device.
-message SizeMessage {
-  optional uint64 width = 1;
-  optional uint64 height = 2;
+// Contains Client->Engine information to establish a authenticated connection.
+message StartConnectionMessage {
+  optional string auth_token = 1;

[maniscalco, 2015/12/02 17:09:35]

Elsewhere we've called this client_token.  I suggest using that name here for
consistency.

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

Done.

+  optional int32 protocol_version = 2;

[maniscalco, 2015/12/02 17:09:35]

Elsewhere this is defined as a string.

[haibinlu, 2015/12/03 01:53:22]

use int per offline discussion.

+  // TODO(haibinlu): add checkpoints.
 }
-