Make scrollAnimatorEnabled work on Mac like it does on other platforms

ui/gfx/animation/animation_win.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 "ui/gfx/animation/animation.h"
+
+#include "base/win/windows_version.h"
+
+namespace gfx {
+
+// static
+bool Animation::ShouldRenderRichAnimation() {
+  if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
+    BOOL result;
+    // Get "Turn off all unnecessary animations" value.
+    if (::SystemParametersInfo(SPI_GETCLIENTAREAANIMATION, 0, &result, 0)) {
+      return !!result;
+    }
+  }
+  return !::GetSystemMetrics(SM_REMOTESESSION);
+}
+
+// static
+bool Animation::ScrollAnimationsEnabledBySystem() {
+  return ShouldRenderRichAnimation();
+}
+
+} // namespace gfx