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

chromeos/system/devicemode.cc

Index: chromeos/system/devicemode.cc
diff --git a/chromeos/system/devicemode.cc b/chromeos/system/devicemode.cc
new file mode 100644
index 0000000000000000000000000000000000000000..01b82fd57284afaf7c42c697f2742c2c522ca17a
--- /dev/null
+++ b/chromeos/system/devicemode.cc
@@ -0,0 +1,21 @@
+// 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