logdog: Add bundler library.

client/internal/logdog/butler/bundler/doc.go

Index: client/internal/logdog/butler/bundler/doc.go
diff --git a/client/internal/logdog/butler/bundler/doc.go b/client/internal/logdog/butler/bundler/doc.go
new file mode 100644
index 0000000000000000000000000000000000000000..fe8679a4a9453fa65cb24de66700eabab945bc5b
--- /dev/null
+++ b/client/internal/logdog/butler/bundler/doc.go
@@ -0,0 +1,25 @@
+// 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.
+
+// Package bundler exports the Bundler interface and its implementation, as well
+// as supporting interfaces.
+//
+// A Bundler is responsible for efficiently buffering and clustering LogDog
+// Butler protobufs together for output. It primarily focused on two protobufs:

[tandrii(chromium), 2015/08/11 18:31:05]

nit: It *is* primarily...

[dnj (Google), 2015/08/12 03:20:09]

Done.

[dnj, 2015/09/02 01:58:14]

Done.

+//   - The ButlerLogBundle_Entry, which represents a series of logs and
+//     metadata belongining to a single stream.

[tandrii(chromium), 2015/08/11 18:31:05]

s/belongining/belonging

[dnj (Google), 2015/08/12 03:20:09]

Done.

[dnj, 2015/09/02 01:58:14]

Done.

+//   - The LogEntry, which is a single chunk of unqualified log data.
+//
+// These protobufs comprise log data, and are grouped together for export in
+// a ButlerLogBundle protobuf.
+//
+// A ButlerLogBundle_Entry will be exported if it matches ANY of the following
+// conditions:
+//   - It has attached log data.
+//   - It has terminal information.
+//
+// Since LogDog outputs can be size-constrained, the Bundler tracks the expected
+// aggregate buffered protobuf size and, on export, breaks the buffered
+// protobufs into bundles along a size threshold boundary.
+package bundler