Alternative to @hide FLAG_RECEIVER_INCLUDE_BACKGROUND

Implementing an alternative to sending broadcast with @hide flag
FLAG_RECEIVER_INCLUDE_BACKGROUND. Instead of using the flag, find the
list of registered broadcast receivers and send them directed broadcasts
to wake them up.

This follows the logic in ag/10055770

Bug: 149090705
Test: m
Test: fastboot flashall
Test: ensure broadcast is received by inspecting logcat
Change-Id: I978cd6481401eb68b26f482e19e412657a0da13c