Scroll AllApps to top when new padding is set.

Bug: 198212488
Test: presubmit
Change-Id: I084939e3c7685531c56b1478887fd872e0e101e9
diff --git a/src/com/android/launcher3/allapps/AllAppsContainerView.java b/src/com/android/launcher3/allapps/AllAppsContainerView.java
index e779ee8..e659aba 100644
--- a/src/com/android/launcher3/allapps/AllAppsContainerView.java
+++ b/src/com/android/launcher3/allapps/AllAppsContainerView.java
@@ -624,6 +624,9 @@
         for (int i = 0; i < mAH.length; i++) {
             mAH[i].padding.top = padding;
             mAH[i].applyPadding();
+            if (mAH[i].recyclerView != null) {
+                mAH[i].recyclerView.scrollToTop();
+            }
         }
         mHeaderTop = mHeader.getTop();
     }
diff --git a/src/com/android/launcher3/allapps/FloatingHeaderRow.java b/src/com/android/launcher3/allapps/FloatingHeaderRow.java
index 9bf6043..6ff2132 100644
--- a/src/com/android/launcher3/allapps/FloatingHeaderRow.java
+++ b/src/com/android/launcher3/allapps/FloatingHeaderRow.java
@@ -47,6 +47,8 @@
 
     /**
      * Scrolls the content vertically.
+     * @param scroll scrolled distance in pixels for active recyclerview.
+     * @param isScrolledOut bool to determine if row is scrolled out of view
      */
     void setVerticalScroll(int scroll, boolean isScrolledOut);