Settings: fix storage measurement for device without emulated sdcard

StorageMeasurement: misc files should only be measured for internal
storage only if it is the emulated storage, otherwise misc count
for the primary storage will be erroneously duplicated on the
internal storage count.

StorageVolumePreferenceCategory:
  - Always create mMountTogglePreference to avoid null pointer
    exception for code that relies on it existing
  - Check if the keys exist before calculating totalValues to
    avoid null pointer exception on storage where media is not
    calculated
  - For available/readonly, set title, not summary (summary is
    supposed to be the amount available)

Change-Id: Ib217f79ee562dffc514696fff038e58ed0dba7d9
Add rom_version
Fix rom_version

Change-Id: I171accab7533c452345d6d739f9b276f370a5eff
Add Themes support

Change-Id: I0eb669956d9e89bb92cd43487b14b4246454a400

Conflicts:
	res/values/strings.xml
	res/xml/settings_headers.xml