Move UdevDecodeString from media/midi to device/udev_linux

device/udev_linux/udev.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 DEVICE_UDEV_LINUX_UDEV_H_
 #define DEVICE_UDEV_LINUX_UDEV_H_
 
 #include <stdarg.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ skipping 61 matching lines @@
     void (*log_fn)(struct udev* udev, int priority, const char* file, int line,
                    const char* fn, const char* format, va_list args));
 void udev_set_log_priority(struct udev* udev, int priority);
 void udev_unref(udev* udev);
 
 // Calls udev_device_get_property_value() and replaces missing values with
 // the empty string.
 std::string UdevDeviceGetPropertyValue(udev_device* udev_device,
                                        const char* key);
 
+// Decodes udev-encoded string. Useful for decoding "*_ENC" udev properties.
+std::string UdevDecodeString(const std::string& encoded);
+
 }  // namespace device
 
 #endif  // DEVICE_UDEV_LINUX_UDEV_H_