Initial support for native accessibility in ARC

components/exo/shell_surface.cc

Index: components/exo/shell_surface.cc
diff --git a/components/exo/shell_surface.cc b/components/exo/shell_surface.cc
index 40fd30b14503b90eabadc448c3f7b96f2369cece..4f48a31e2a0f89c349611ad2bfb010e612113281 100644
--- a/components/exo/shell_surface.cc
+++ b/components/exo/shell_surface.cc
@@ -22,6 +22,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
+#include "components/exo/ax_tree_source_surface.h"
 #include "components/exo/surface.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/cursor_client.h"
@@ -871,6 +872,14 @@ gfx::Size ShellSurface::GetMinimumSize() const {
   return gfx::Size(1, 1);
 }
 
+void ShellSurface::GetAccessibleNodeData(ui::AXNodeData* node_data) {
+  if (surface_ && surface_->ax_tree_source()) {
+    ui::AXTreeData data;
+    surface_->ax_tree_source()->GetTreeData(&data);
+    node_data->AddIntAttribute(ui::AX_ATTR_CHILD_TREE_ID, data.tree_id);
+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // ash::wm::WindowStateObserver overrides: