cc: Add a rails argument to InputHandler::ScrollBy

cc/trees/layer_tree_host_unittest_scroll.cc

Index: cc/trees/layer_tree_host_unittest_scroll.cc
diff --git a/cc/trees/layer_tree_host_unittest_scroll.cc b/cc/trees/layer_tree_host_unittest_scroll.cc
index be972e9406e7de12ac7f7d9f453d3677e716f3fe..fc8bc4ceda6be8830738858d40f8ce2e3461de65 100644
--- a/cc/trees/layer_tree_host_unittest_scroll.cc
+++ b/cc/trees/layer_tree_host_unittest_scroll.cc
@@ -593,7 +593,8 @@ class LayerTreeHostScrollTestCaseWithChild : public LayerTreeHostScrollTest {
                                gfx::Vector2dF(0.5f, 0.5f)),
             InputHandler::GESTURE);
         EXPECT_EQ(InputHandler::SCROLL_STARTED, status);
-        impl->ScrollBy(gfx::Point(), scroll_amount_);
+        impl->ScrollBy(gfx::Point(), scroll_amount_,
+                       InputHandler::RAILS_MODE_FREE);
         impl->ScrollEnd();
 
         // Check the scroll is applied as a delta.
@@ -610,7 +611,8 @@ class LayerTreeHostScrollTestCaseWithChild : public LayerTreeHostScrollTest {
                                gfx::Vector2dF(0.5f, 0.5f)),
             InputHandler::WHEEL);
         EXPECT_EQ(InputHandler::SCROLL_STARTED, status);
-        impl->ScrollBy(gfx::Point(), scroll_amount_);
+        impl->ScrollBy(gfx::Point(), scroll_amount_,
+                       InputHandler::RAILS_MODE_FREE);
         impl->ScrollEnd();
 
         // Check the scroll is applied as a delta.