Perform state switch to Overview from -1 screen

- This fixed a regression caused by ag/27904180, where -1 is no longer considered `visibleLauncher`. -1 still have Launcher being top activity, and recents animation will always fail
- Added isInMinusOne in LauncherActivityInterface, and return Launcher in getVisibleLauncher for -1 case
- -1 should be the only case where Launcher is top activity, but is not started

Fix: 352254279
Test: Recents button from the following scenarios: Home, -1, apps, transparent apps, video from -1
Flag: EXEMPT bugfix
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:1cd3fe27f229da4f7bb80a2e04d1416cc050fc94)
Merged-In: I0898d202b9dd4742c0c7d2c0d6b340c748e8acf7
Change-Id: I0898d202b9dd4742c0c7d2c0d6b340c748e8acf7