Move V4L2 code into a webcam helper class.

extensions/browser/api/webcam_private/webcam.cc

Index: extensions/browser/api/webcam_private/webcam.cc
diff --git a/extensions/browser/api/webcam_private/webcam.cc b/extensions/browser/api/webcam_private/webcam.cc
new file mode 100644
index 0000000000000000000000000000000000000000..79b65105bb4dbe92ee4a2b62ff0c27cb4a4c14c4
--- /dev/null
+++ b/extensions/browser/api/webcam_private/webcam.cc
@@ -0,0 +1,12 @@
+// Copyright 2015 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 "extensions/browser/api/webcam_private/webcam.h"
+
+namespace extensions {
+
+Webcam::Webcam() {}
+Webcam::~Webcam() {}
+
+}  // namespace extensions