Move UnionDecorationHandler to Launcher

- Create base SectionDecorationInfo.java and RecyclerViewAnimationController.java
- SearchTransitionController now inherits from RecyclerViewAnimationController where RecyclerViewAnimationController will control
animation for private space

Bug: 299294792
Test: Verified SearchTransitionController didn't regress by turning off BACKGROUND_DRAWABLES flag.
- Verified QL highlight still works
- video: https://drive.google.com/file/d/15yjBWofebn6m7VgEnLK6kEYqhC_adJQ3/view?usp=sharing

Flag: None
Change-Id: If34f4bb199be0e113485279931d2927cb9fad397

src/com/android/launcher3/allapps/ActivityAllAppsContainerView.java

@@ -407,7 +407,7 @@ public class ActivityAllAppsContainerView<T extends Context & ActivityContext>
             // If exiting search, revert predictive back scale on all apps
             mAllAppsTransitionController.animateAllAppsToNoScale();
         }
-        mSearchTransitionController.animateToSearchState(goingToSearch, durationMs,
+        mSearchTransitionController.animateToState(goingToSearch, durationMs,
                 /* onEndRunnable = */ () -> {
                     mIsSearching = goingToSearch;
                     updateSearchResultsVisibility();