base: Add theme support to Ringtone picker activitiy

Patchset 3: Add support for theme RingtonePreference view. The dialog is
            automatically adjusted to the caller activity base theme.
Patchset 4: Don't break the android api

For Ringtones:

http://review.cyanogenmod.org/#/c/61393/

For Profiles:

Usage:

Intent intent = new Intent(ProfileManager.ACTION_PROFILE_PICKER);
intent.putExtra(ProfileManager.EXTRA_PROFILE_DIALOG_THEME, R.style.CustomDialogTheme); <<< Add your custom dialog theme here
startActivityForResult(intent, 0);

Style Usage:

Define an style that inherits from an android base theme

<style name="CustomDialogThemeDark" parent="@*android:style/Theme.Holo.Dialog.Alert">

or

<style name="CustomDialogThemeLight" parent="@*android:style/Theme.Holo.Light.Dialog.Alert">

or define your own dialog style

Change-Id: Icadbcf2c617c51177466989acdab9435066a47a0
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
FileUtils: add method to get UUID of a volume

Change-Id: I41b76c5e01c82a2f8e67b33133a76947877a2814