Properly scale the coordinate for TouchSelection when use-zoom-for-dsf mode is on.

cc/trees/layer_tree_impl.cc

Index: cc/trees/layer_tree_impl.cc
diff --git a/cc/trees/layer_tree_impl.cc b/cc/trees/layer_tree_impl.cc
index a4d3e4782aa46f56826a4f9c751cc99182cb0b77..8dfae9e1f93015c865f7989fb11fcc54199e757f 100644
--- a/cc/trees/layer_tree_impl.cc
+++ b/cc/trees/layer_tree_impl.cc
@@ -1809,12 +1809,11 @@ static ViewportSelectionBound ComputeViewportSelectionBound(
 
 void LayerTreeImpl::GetViewportSelection(ViewportSelection* selection) {
   DCHECK(selection);
-
   selection->start = ComputeViewportSelectionBound(
       selection_.start,
       selection_.start.layer_id ? LayerById(selection_.start.layer_id) : NULL,
-      device_scale_factor(), property_trees_.transform_tree,
-      property_trees_.clip_tree);
+      device_scale_factor() * painted_device_scale_factor(),
+      property_trees_.transform_tree, property_trees_.clip_tree);
   selection->is_editable = selection_.is_editable;
   selection->is_empty_text_form_control = selection_.is_empty_text_form_control;
   if (selection->start.type == SELECTION_BOUND_CENTER ||
@@ -1824,8 +1823,8 @@ void LayerTreeImpl::GetViewportSelection(ViewportSelection* selection) {
     selection->end = ComputeViewportSelectionBound(
         selection_.end,
         selection_.end.layer_id ? LayerById(selection_.end.layer_id) : NULL,
-        device_scale_factor(), property_trees_.transform_tree,
-        property_trees_.clip_tree);
+        device_scale_factor() * painted_device_scale_factor(),
+        property_trees_.transform_tree, property_trees_.clip_tree);
   }
 }