Delete some dead code.

ui/accessibility/ax_tree_unittest.cc

Index: ui/accessibility/ax_tree_unittest.cc
diff --git a/ui/accessibility/ax_tree_unittest.cc b/ui/accessibility/ax_tree_unittest.cc
index 7dcf59e2a8a51b138a6528f1e238c30ee65c822e..f4c609ed36b4cea2909302ada79aead060bc3aac 100644
--- a/ui/accessibility/ax_tree_unittest.cc
+++ b/ui/accessibility/ax_tree_unittest.cc
@@ -32,16 +32,8 @@ class FakeAXTreeDelegate : public AXTreeDelegate {
     new_root_ids_.push_back(new_root->id());
   }
 
-  void Reset() {
-    deleted_ids_.clear();
-    created_ids_.clear();
-    changed_ids_.clear();
-    new_root_ids_.clear();
-  }
-
   const std::vector<int32>& deleted_ids() { return deleted_ids_; }
   const std::vector<int32>& created_ids() { return created_ids_; }
-  const std::vector<int32>& changed_ids() { return changed_ids_; }
   const std::vector<int32>& new_root_ids() { return new_root_ids_; }
 
  private: