Frameworks: Fix Lockscreen Blur

PS6: 1. Remove content observer and unnecessary calls from viewManager
     2. Restructure the flow of setting the custom image
         * now closely follows setting album art as lockscreen image

Signed off by : hany <hany@codexc.com>

Change-Id: I19cab7f88935da132041b6a967ebd6d1a9fc04d8
Fix: Lockscreen Blur Rotation

Change-Id: I857e88e6cfffa71a7052c6b418c8db2022e5f253