wifi: Allow configuration of country code for wifi (2/2)

Wifi country code handling is a nightmare - Most retail devices
have region customization in /system for each country a device
is shipped to.

This doesn't work very well for a firmware like Cyanogenmod,
where we try to support all target countries with one firmware
package.  For whatever reason, with newer Broadcom drivers/
firmware blobs, the old trick of using a universal region code
(ccode=ALL in nvram_net.txt) does not seem to work.  Who knows
what the deal is for other wifi chipsets.

The good thing is that wpa_supplicant has a standardized
cross-chipset method for setting the region code, and we
use that here.

Ported from cm-10.2
Framework part: http://review.cyanogenmod.org/54997

Change-Id: Ia9f5133f61f56d89ccb290e37a393f5de507e1cf

Conflicts:
	res/values/arrays_custom.xml

Conflicts:

	res/values/strings_custom.xml
Settings: Fix the memory leak in Settings

Fixed the memory leak in both InstalledAppDetails

Change-Id: I3520b3c1fe1bf98e3baec2ee989eb215164a7cf2
Signed-off-by: Zhijun Peng <pengzhj@marvell.com>
Total and available fields missing in Settings storage menu

After formatting SD card or inserting an SD card the total and
available space fields in Settings storage are missing.
This fix add those fields after SD card has been mounted.

Change-Id: Id6c1d1963effdb9656c8eb1c567b913bc4d98bd2
Enable Back-key when go to Emergency call

When go to "Emergency call" from lock screen, back key is disappeared.
It is difficult for user to find the way to go back to previous screen.
This might be bad user experience. So we are going to make it enable.

Change-Id: Iefcca9b8943472c24ddbca6e3ec3441e93e5be91