Update fast scroller item count after layoutChildren()

BUG: 12553181
Change-Id: I4ea1b45d08c153b0146868bf57884d6b8dde6245
diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index 47d42dc..96a2ab5 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -2135,15 +2135,15 @@
             mRecycler.markChildrenDirty();
         }
 
-        // TODO: Move somewhere sane. This doesn't belong in onLayout().
-        if (mFastScroll != null) {
-            mFastScroll.onItemCountChanged(childCount, mItemCount);
-        }
-
         layoutChildren();
         mInLayout = false;
 
         mOverscrollMax = (b - t) / OVERSCROLL_LIMIT_DIVISOR;
+
+        // TODO: Move somewhere sane. This doesn't belong in onLayout().
+        if (mFastScroll != null) {
+            mFastScroll.onItemCountChanged(getChildCount(), mItemCount);
+        }
     }
 
     /**