Fix external bug http://code.google.com/p/android/issues/detail?id=15183

Prevent overflow in FastScroller indexing

Change-Id: I53f90feaefd49717a0bdaddcf9a4988318d40c7d

core/java/android/widget/FastScroller.java

@@ -564,6 +564,9 @@ class FastScroller {
             }
         } else {
             int index = (int) (position * count);
+            // Don't overflow
+            if (index > count - 1) index = count - 1;
+
             if (mList instanceof ExpandableListView) {
                 ExpandableListView expList = (ExpandableListView) mList;
                 expList.setSelectionFromTop(expList.getFlatListPosition(