Do proper Doze white-listing in UI tests

briar-android/proguard-test.txt

.../org/briarproject/briar/android/TestBriarApplication.java

...st/java/org/briarproject/briar/android/TestComponent.java

...roject/briar/android/navdrawer/NavDrawerActivityTest.java

...rproject/briar/android/settings/SettingsActivityTest.java

.../org/briarproject/briar/android/test/BriarTestRunner.java

...a/org/briarproject/briar/android/test/ScreenshotTest.java

...java/org/briarproject/briar/android/test/ViewActions.java

...ain/java/org/briarproject/briar/android/util/UiUtils.java