Smooth scroll to advanced/ basic.

Currently, the animation doesn't look better.
But when the rest of b/6516391 Selecting 'advanced panel' in overflow menu is janky
is fixed, it should

Change-Id: If0db9bbb3ef87d99be174a256e82cde2ee54f587
diff --git a/src/com/android/calculator2/Calculator.java b/src/com/android/calculator2/Calculator.java
index 18b676c..f63b190 100644
--- a/src/com/android/calculator2/Calculator.java
+++ b/src/com/android/calculator2/Calculator.java
@@ -203,13 +203,13 @@
 
             case R.id.basic:
                 if (!getBasicVisibility() && mPager != null) {
-                    mPager.setCurrentItem(BASIC_PANEL);
+                    mPager.setCurrentItem(BASIC_PANEL, true);
                 }
                 break;
 
             case R.id.advanced:
                 if (!getAdvancedVisibility() && mPager != null) {
-                    mPager.setCurrentItem(ADVANCED_PANEL);
+                    mPager.setCurrentItem(ADVANCED_PANEL, true);
                 }
                 break;
         }