Blacklist: Avoid crash when dialog dismissed via back button.

A user usually presses the back button only
when he/she does not want the changes to be saved.
Hence we need to revert the changes that took place
when the dialog is dismissed with back button.

Change-Id: Ifa3ef41f02f11d1e1627071532d8f915e3b445b6
Merge branch 'kitkat' of https://github.com/AOSPA/android_packages_apps_Settings into AOSPA-kitkat

# By sd3993
# Via sd3993
* 'kitkat' of https://github.com/AOSPA/android_packages_apps_Settings:
  Blacklist: Avoid crash when dialog dismissed via back button.
Merge branch 'AOSPA-kitkat' into AOSCP-4.4.3

* AOSPA-kitkat:
  Blacklist: Avoid crash when dialog dismissed via back button.
Merge branch 'AOSCP-4.4.3' of https://github.com/AOSCP/platform_packages_apps_settings into AOSCP-4.4.3

* 'AOSCP-4.4.3' of https://github.com/AOSCP/platform_packages_apps_settings:
  Settings: fix merge derp's