Extend AXTreeSourceViews to handle aura::Window and views::Widget.

chrome/browser/ui/views/accessibility/ax_root_obj_wrapper.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 "chrome/browser/ui/views/accessibility/ax_root_obj_wrapper.h"
+
+#include "ash/shell.h"
+#include "ui/accessibility/ax_node_data.h"
+#include "ui/accessibility/ax_view_state.h"
+#include "ui/aura/window.h"
+#include "ui/views/accessibility/ax_aura_obj_cache.h"
+
+AXRootObjWrapper::AXRootObjWrapper(int32 id) : id_(id) {
+}
+
+AXRootObjWrapper::~AXRootObjWrapper() {}
+
+bool AXRootObjWrapper::HasChild(views::AXAuraObjWrapper* child) {
+  std::vector<views::AXAuraObjWrapper*> out_children;

[aboxhall, 2014/04/28 19:50:38]

Why is this called out_children? It's never sent out of the scope of this
function. I realise it's passed to GetChildren below, but I think it would be
less confusing to call it simply 'children' (and as a bonus the return statement
would fit on one line that way).

[David Tseng, 2014/04/29 01:35:03]

I don't have a strong opinion here, but as you noted, it is an out parameter to
GetChildren (and the convention is to prefix without_, at least for parameter
names).

[aboxhall, 2014/04/29 02:19:23]

I find it confusing, as I would expect out_foo to be an argument to the current
function (an out parameter) or else a parameter to an IPC or similar (this seems
to be the vast majority of cases when I search the codebase for "\bout_\w+"). In
the context of the implementation of GetChildren I would expect the argument to
be called out_children, but in the context of the caller it doesn't make sense
to me to call it that.

+  GetChildren(&out_children);
+  return std::find(out_children.begin(), out_children.end(), child) !=
+      out_children.end();
+}
+
+views::AXAuraObjWrapper* AXRootObjWrapper::GetParent() {
+  return NULL;
+}
+
+void AXRootObjWrapper::GetChildren(
+    std::vector<views::AXAuraObjWrapper*>* out_children) {
+  aura::Window::Windows children =
+      ash::Shell::GetInstance()->GetAllRootWindows();
+  for (size_t i = 0; i < children.size(); ++i) {
+    out_children->push_back(
+        views::AXAuraObjCache::GetInstance()->GetOrCreate(children[i]));
+  }
+}
+
+void AXRootObjWrapper::Serialize(ui::AXNodeData* out_node_data) {
+  out_node_data->id = id_;
+  out_node_data->role = ui::AX_ROLE_DESKTOP;
+  out_node_data->state = 0;

[aboxhall, 2014/04/28 19:50:38]

Is |state| not guaranteed to be initialized to 0? Should that be the
responsibility of the caller or the struct constructor instead?

[David Tseng, 2014/04/29 01:35:03]

AXNodeData sets state to -1.

However, the root should have some better notion of state here, so I've added a
TODO.

+}
+
+int32 AXRootObjWrapper::GetID() {
+  return id_;
+}