Helium: Initial proto and Syncable interface definition

blimp/net/helium/syncable.cc

Index: blimp/net/helium/syncable.cc
diff --git a/blimp/net/helium/syncable.cc b/blimp/net/helium/syncable.cc
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index 0000000000000000000000000000000000000000..a6b8a7d4211f207010035db497eb57813fd5a671
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+++ b/blimp/net/helium/syncable.cc
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+// Copyright 2016 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.
+
+#include "blimp/net/helium/syncable.h"
+
+namespace blimp {
+
+SyncableObject::SyncableObject(const VectorClock& clock) : clock_(clock) {}
+
+template <class ChangesetType>
+SyncableMember<ChangesetType>::SyncableMember(SyncableObject* parent)
+    : parent_(parent) {}
+
+template <class ChangesetType>
+VectorClock SyncableMember<ChangesetType>::IncrementParentClock() {
+  parent_->get_clock().IncrementLocal();
+  return parent_->get_clock();
+}
+
+// Instantiate the template for int (Unit test uses it)

[Kevin M, 2016/09/30 18:34:36]

This approach doesn't scale - unit tests need it for now, but in the future,
we'll need to update this list for all product callers as well.

Put the templated code inline in the .h instead. If there is substantial common
code that is template type agnostic, we can use helper functions, or a
non-templated base class. For small method bodies, don't bother.

[scf, 2016/09/30 22:13:23]

Done.

+template class Syncable<int>;
+template class Syncable<helium::Changeset>;
+template class SyncableMember<helium::Changeset>;
+template class SyncableMember<int>;
+
+}  // namespace blimp