ui/base/models: convert usage of FOR_EACH_OBSERVER macro

ui/base/models/tree_node_model.h

Index: ui/base/models/tree_node_model.h
diff --git a/ui/base/models/tree_node_model.h b/ui/base/models/tree_node_model.h
index 3cb290a3bec37979c6dfc8dfdc6041d153042bb4..a61abd98f5fefea7e10fdee51ea9c8da13a88250 100644
--- a/ui/base/models/tree_node_model.h
+++ b/ui/base/models/tree_node_model.h
@@ -229,21 +229,18 @@ class TreeNodeModel : public TreeModel {
   }
 
   void NotifyObserverTreeNodesAdded(NodeType* parent, int start, int count) {
-    FOR_EACH_OBSERVER(TreeModelObserver,
-                      observer_list_,
-                      TreeNodesAdded(this, parent, start, count));
+    for (TreeModelObserver& observer : observer_list_)
+      observer.TreeNodesAdded(this, parent, start, count);
   }
 
   void NotifyObserverTreeNodesRemoved(NodeType* parent, int start, int count) {
-    FOR_EACH_OBSERVER(TreeModelObserver,
-                      observer_list_,
-                      TreeNodesRemoved(this, parent, start, count));
+    for (TreeModelObserver& observer : observer_list_)
+      observer.TreeNodesRemoved(this, parent, start, count);
   }
 
   void NotifyObserverTreeNodeChanged(TreeModelNode* node) {
-    FOR_EACH_OBSERVER(TreeModelObserver,
-                      observer_list_,
-                      TreeNodeChanged(this, node));
+    for (TreeModelObserver& observer : observer_list_)
+      observer.TreeNodeChanged(this, node);
   }
 
   // TreeModel: