Merging ub-launcher3-qt-qpr1-dev, build 5884665

Test: Manual

Bug:135864059 P4 [Live Tiles] Empty launcher
Bug:139137636 P2 Create memory tests for Launcher
Bug:139281702 P2 [Enterprise - Cloud DO] GSOC and Mobile Utilities launcher icons are in broken state
Bug:140837771 P1 Failing test: AddConfigWidgetTests and AddWidgetTests are failing
Bug:141024521 P2 Tapping nav bar during quick switch causes scroll animation to cancel and not resume
Bug:141184247 P1 Clear all button not present in fallback recents in 3-button mode
Change-Id: I99f4db995a2af5959d5be4182f4e47bb67c9cbc4