Fix janky transition on All Apps tab switch

Bug: 7139562
diff --git a/src/com/android/launcher2/AppsCustomizeTabHost.java b/src/com/android/launcher2/AppsCustomizeTabHost.java
index 96ec33e..19bc682 100644
--- a/src/com/android/launcher2/AppsCustomizeTabHost.java
+++ b/src/com/android/launcher2/AppsCustomizeTabHost.java
@@ -282,10 +282,15 @@
                         reloadCurrentPage();
                     }
                 });
-                AnimatorSet animSet = LauncherAnimUtils.createAnimatorSet();
+
+                final AnimatorSet animSet = LauncherAnimUtils.createAnimatorSet();
                 animSet.playTogether(outAnim, inAnim);
                 animSet.setDuration(duration);
-                animSet.start();
+                post(new Runnable() {
+                    public void run() {
+                        animSet.start();
+                    }
+                });
             }
         });
     }