Resolve account image icon profile boundary exploit.

Because Telecom grants the INTERACT_ACROSS_USERS permission, an exploit
is possible where the user can upload an image icon (belonging to
another user) via registering a phone account. This CL provides a
lightweight solution for parsing the image URI to detect profile
exploitation.

Fixes: 273502295
Test: Unit test to enforce successful/failure path
Change-Id: I2b6418f019a373ee9f02ba8683e5b694e7ab80a5