Override the overscroll color for the widget rows.

Change-Id: I249e13f511736ad9e874800a1b9ee1f8602434f4

res/layout/widgets_list_row_view.xml

@@ -51,6 +51,7 @@
 
     <HorizontalScrollView
         android:id="@+id/widgets_scroll_container"
+        android:theme="@style/Theme.Dark.CustomOverscroll"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:scrollbars="none">