Add more tests for restricted broadcasts.

Test that certain wifi broadcasts are properly protected by the system.
This detects the presence of a security bug which allows the modification
of wifi proxy settings.

This list was taken from frameworks/base commit
47918ae3b4e7ebb54711884e9ff9d0300591ab8b

Public Bug: http://code.google.com/p/android/issues/detail?id=40506
Bug: 7622253

(cherry picked from commit 7993485b)

Change-Id: I69478b20975c09f87914ba04d0a7009aa6ef6c88