am 737552d7: Merge "Big refactor, additions to state transition animations" into gb-ub-photos-arches

* commit '737552d7925366c58067d622e1b8df06786c51cc':
  Big refactor, additions to state transition animations
tree: 8e174fb53f5575c1e51bb9d1d1064800f625d413
  1. gallerycommon/
  2. src/
  3. src_pd/
  4. tests/