accessibility: Simpler AXTree root accessor.

ui/accessibility/ax_tree_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/accessibility/ax_node.h"
 #include "ui/accessibility/ax_serializable_tree.h"
 #include "ui/accessibility/ax_tree.h"
@@ skipping 96 matching lines @@
   AXTreeUpdate initial_state;
   initial_state.nodes.push_back(root);
   initial_state.nodes.push_back(button);
   initial_state.nodes.push_back(checkbox);
   AXSerializableTree src_tree(initial_state);
 
   scoped_ptr<AXTreeSource<const AXNode*> > tree_source(
       src_tree.CreateTreeSource());
   AXTreeSerializer<const AXNode*> serializer(tree_source.get());
   AXTreeUpdate update;
-  serializer.SerializeChanges(src_tree.GetRoot(), &update);
+  serializer.SerializeChanges(src_tree.root(), &update);
 
   AXTree dst_tree;
   ASSERT_TRUE(dst_tree.Unserialize(update));
 
-  const AXNode* root_node = dst_tree.GetRoot();
+  const AXNode* root_node = dst_tree.root();
   ASSERT_TRUE(root_node != NULL);
   EXPECT_EQ(root.id, root_node->id());
   EXPECT_EQ(root.role, root_node->data().role);
 
   ASSERT_EQ(2, root_node->child_count());
 
   const AXNode* button_node = root_node->ChildAtIndex(0);
   EXPECT_EQ(button.id, button_node->id());
   EXPECT_EQ(button.role, button_node->data().role);
 
@@ skipping 188 matching lines @@
 
   ASSERT_EQ(1U, fake_delegate.node_creation_finished_ids().size());
   EXPECT_EQ(4, fake_delegate.node_creation_finished_ids()[0]);
 
   ASSERT_EQ(true, fake_delegate.root_changed());
 
   tree.SetDelegate(NULL);
 }
 
 }  // namespace ui