Lock screen: Add see through and blur, (1/2):

Thanks to OmniRom:
https://github.com/omnirom/android_frameworks_base/commit/2017828cdbbef1f673226f0fce5da8eb636f898d
https://github.com/omnirom/android_frameworks_base/commit/a62bf77cef156678835412206e685b78a720c5ab
https://github.com/omnirom/android_frameworks_base/commit/a2e406d1167e5e7f36387d00528759df099abfe0
https://github.com/omnirom/android_frameworks_base/commit/a2e406d1167e5e7f36387d00528759df099abfe0