Add an internal state test to ImportantNoticeUtilsTests

On some 32bit-x86 testing emulators, it seems the internal state after
clear the related settings seems like a contradiction state. This CL
adds an test to check such internal state in order to investigate what
is happening on these emulators.

Bug: 17635340
Change-Id: Iba85f06c46959b1dc22e2a9213c50c9e7e30949b