ozone: Allow ozone evdev/kvm features to be enabled without running on ChromeOS.

chromeos/system/devicemode.cc

+// Copyright 2017 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 "chromeos/system/devicemode.h"
+
+#include "base/command_line.h"
+#include "base/sys_info.h"
+#include "chromeos/chromeos_switches.h"
+
+namespace chromeos {
+
+bool IsRunningAsSystemCompositor() {
+  static bool is_running_as_system_compositor =
+      base::SysInfo::IsRunningOnChromeOS() ||
+      base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kForceSystemCompositorMode);
+  return is_running_as_system_compositor;
+}
+
+}  // namespace chromeos