views: add focus ring to TreeView

ui/views/controls/tree/tree_view.h

Index: ui/views/controls/tree/tree_view.h
diff --git a/ui/views/controls/tree/tree_view.h b/ui/views/controls/tree/tree_view.h
index 5eb096e3d2fb4f04d33cdfb68180c05f5342992f..6163806790fc22da594aacf62f0a162ed5289fba 100644
--- a/ui/views/controls/tree/tree_view.h
+++ b/ui/views/controls/tree/tree_view.h
@@ -24,9 +24,10 @@ class Rect;
 
 namespace views {
 
+class PrefixSelector;
+class ScrollView;
 class Textfield;
 class TreeViewController;
-class PrefixSelector;
 
 // TreeView displays hierarchical data as returned from a TreeModel. The user
 // can expand, collapse and edit the items. A Controller may be attached to
@@ -349,6 +350,11 @@ class VIEWS_EXPORT TreeView : public View,
   // control.
   bool IsPointInExpandControl(InternalNode* node, const gfx::Point& point);
 
+  // Sets whether a focus ring is visible on this control or not. This function
+  // does nothing if focus rings aren't enabled in general or if the platform's
+  // style does not use focus rings on TreeViews.
+  void SetHasFocusRing(bool);
+
   // The model, may be null.
   ui::TreeModel* model_;