Abstracting StatefulActivity from StateManager

Flag: NONE - abstraction with no logic changes.

Test: Built and ran locally, for launcher3 and third party launchers

Bug: 224595066

Change-Id: I9da15bdd649d3a20e98c6552bb9e9abaec72f97f
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 6c9d4c0..4e566ab 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -312,7 +312,7 @@
 
     private static boolean sIsNewProcess = true;
 
-    private StateManager<LauncherState> mStateManager;
+    private StateManager<LauncherState, Launcher> mStateManager;
 
     private static final int ON_ACTIVITY_RESULT_ANIMATION_DELAY = 500;
 
@@ -2775,7 +2775,7 @@
     }
 
     @Override
-    protected void collectStateHandlers(List<StateHandler> out) {
+     public void collectStateHandlers(List<StateHandler<LauncherState>> out) {
         out.add(getAllAppsController());
         out.add(getWorkspace());
     }
@@ -2996,7 +2996,7 @@
     }
 
     @Override
-    public StateManager<LauncherState> getStateManager() {
+    public StateManager<LauncherState, Launcher> getStateManager() {
         return mStateManager;
     }