Revert "SystemUI: fix RecentPanel position in landscape mode."

This reverts commit d3ed464b2ce9489bbb8f674b25aaec31eecaa254.
Revert "Move clear all button on the top-right"

This reverts commit 93717f71255825ad2218eae1c57b9a97c321cab2.
Revert "Clear all recents button"

This reverts commit b535727adf8d960f3a7854fb42094ee18367e1ea.
Revert "Revert "Recents: Clear all button for recent apps.""

This reverts commit 7973baa366b5c1fca4bb211b8d65cb32d5fa2721.