Prune invisible views from the desktop automation tree

chrome/browser/ui/ash/accessibility/ax_tree_source_aura_unittest.cc

 // Copyright 2014 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 <stddef.h>
 
 #include <vector>
 
 #include "ash/test/ash_test_base.h"
 #include "base/macros.h"
@@ skipping 47 matching lines @@
     Widget::InitParams init_params(Widget::InitParams::TYPE_POPUP);
     init_params.parent = CurrentContext();
     widget_->Init(init_params);
 
     content_ = new View();
     widget_->SetContentsView(content_);
 
     textfield_ = new Textfield();
     textfield_->SetText(base::ASCIIToUTF16("Value"));
     content_->AddChildView(textfield_);
+    widget_->Show();
   }
 
  protected:
   Widget* widget_;
   View* content_;
   Textfield* textfield_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AXTreeSourceAuraTest);
 };
@@ skipping 80 matching lines @@
 
   // Now, re-serialize.
   ui::AXTreeUpdate out_update2;
   ax_serializer.SerializeChanges(textfield_wrapper, &out_update2);
 
   size_t node_count = out_update2.nodes.size();
 
   // We should have far more updates this time around.
   ASSERT_GE(node_count, 10U);
 
-  ASSERT_EQ(textfield_wrapper->GetID(), out_update2.nodes[node_count - 1].id);
-  ASSERT_EQ(ui::AX_ROLE_TEXT_FIELD, out_update2.nodes[node_count - 1].role);
+  int text_field_update_index = -1;
+  for (size_t i = 0; i < node_count; ++i) {
+    if (textfield_wrapper->GetID() == out_update2.nodes[i].id)
+      text_field_update_index = i;
+  }
+
+  ASSERT_NE(-1, text_field_update_index);
+  ASSERT_EQ(ui::AX_ROLE_TEXT_FIELD,
+            out_update2.nodes[text_field_update_index].role);
 }