Implement ViewDragHelper to pull down history.

Bug: 31623549
Change-Id: Ie5c9bc0afef59f0922bd87bee709d04d294f24b9
diff --git a/res/layout/activity_calculator_land.xml b/res/layout/activity_calculator_land.xml
index 5dd2c20..a19cd86 100644
--- a/res/layout/activity_calculator_land.xml
+++ b/res/layout/activity_calculator_land.xml
@@ -37,4 +37,4 @@
 
     </LinearLayout>
 
-</LinearLayout>
+</LinearLayout>
\ No newline at end of file