Move most of the functions in LauncherAppWidgetHost to LauncherWidgetHolder

Test: N/A
Bug: 235358918
Change-Id: I343419376491203a195154f2766b12e5def38879
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index ab7f622..de2ef55 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -1720,6 +1720,7 @@
         } catch (NullPointerException ex) {
             Log.w(TAG, "problem while stopping AppWidgetHost during Launcher destruction", ex);
         }
+        mAppWidgetHolder.destroy();
 
         TextKeyListener.getInstance().release();
         clearPendingBinds();