Changes Mac removable device listing to include all attached USB drives.

chrome/common/extensions/image_writer/image_writer_util_mac.h

+// Copyright 2014 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.
+
+#ifndef CHROME_COMMON_EXTENSIONS_IMAGE_WRITER_IMAGE_WRITER_UTIL_MAC_H
+#define CHROME_COMMON_EXTENSIONS_IMAGE_WRITER_IMAGE_WRITER_UTIL_MAC_H
+
+#include <IOKit/IOKitLib.h>
+
+namespace extensions {
+
+// Determines whether the object from the IO registry is a USB mass storage
+// device.  It does this by reading the ancestors of the object to see if any
+// is of the USB mass-storage class.
+bool IsUsbDevice(io_object_t disk_obj);
+
+}  // namespace extensions
+
+#endif  // CHROME_COMMON_EXTENSIONS_IMAGE_WRITER_IMAGE_WRITER_UTIL_MAC_H