Add VR Shell animation classes and unit test.

chrome/browser/android/vr_shell/animation.cc

+// 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 "chrome/browser/android/vr_shell/animation.h"
+
+namespace vr_shell {
+
+Animation::Animation(int id,
+                     Property property,
+                     std::unique_ptr<easing::Easing> easing,
+                     std::vector<float> from,
+                     std::vector<float> to,
+                     int64_t start,
+                     int64_t duration)
+    : id(id),
+      property(property),
+      easing(std::move(easing)),
+      from(from),
+      to(to),
+      start(start),
+      duration(duration) {}
+
+Animation::~Animation() {}
+
+}  // namespace vr_shell