Merging ub-launcher3-qt-r1-dev, build 5706291

Test: Manual

Bug:136285765 P2 Update theme picker icons sizes
Bug:136497932 P2 Wallpaper preview color should match the one on homescreen
Change-Id: I96402dd97c9ad0c1e50abb2cce18d4e499530b80
tree: 7b344e1a936ebf39f57152abd55a73dc2cc45397
  1. res/
  2. robolectric_tests/
  3. src/
  4. src_override/
  5. Android.mk
  6. AndroidManifest.xml