The testNotificationsShownAndCleared test was not doing anything
because the list of notification to show was always empty.
This patch fixes this issue and actually makes the test loop on
non-empty collections, and also fixes another ordering issue in
assertions themselves, hidden until now by the first issue.
Bug: 32561414
Test: runtest -x frameworks/base/tests/net/java/com/android/server/connectivity/NetworkNotificationManagerTest.java
Merged-In: I4837b1175d7c9133e9156e33acaa1e7e3341cc62
Change-Id: Ia30587bd68a87b83b62f57eeeb28fef7d95dbf81
(cherry picked from commit 9eec272054)
343091956d