A11y: Add/refactor methods for manipulating bitfields on AXNodeData.

ui/views/accessibility/ax_view_obj_wrapper.cc

Index: ui/views/accessibility/ax_view_obj_wrapper.cc
diff --git a/ui/views/accessibility/ax_view_obj_wrapper.cc b/ui/views/accessibility/ax_view_obj_wrapper.cc
index 2a22590bbb23c404de53e38a8ce868bad966e4cd..e636e34336b45fc8bb362422f408775fe4a6011f 100644
--- a/ui/views/accessibility/ax_view_obj_wrapper.cc
+++ b/ui/views/accessibility/ax_view_obj_wrapper.cc
@@ -46,15 +46,14 @@ void AXViewObjWrapper::GetChildren(
 }
 
 void AXViewObjWrapper::Serialize(ui::AXNodeData* out_node_data) {
-  out_node_data->state = 0;

[sky, 2017/05/08 15:56:27]

How come the new code doesn't need a ClearState() or something? Is it assumed
that Serialize() is called with the state set to 0 already?

[Patti Lor, 2017/05/09 06:03:40]

The current AXNodeData class initialises its |state| member to be 0xffffff,
which was an invalid state (see
https://codereview.chromium.org/2860883003/#msg28 - Dominic's comment - for the
reason if you're interested). This patch is changing it so that it is inited to
0x0 instead, so this is fine :)

   view_->GetAccessibleNodeData(out_node_data);
 
   out_node_data->id = GetID();
 
   if (view_->IsAccessibilityFocusable())
-    out_node_data->state |= 1 << ui::AX_STATE_FOCUSABLE;
+    out_node_data->AddState(ui::AX_STATE_FOCUSABLE);
   if (!view_->visible())
-    out_node_data->state |= 1 << ui::AX_STATE_INVISIBLE;
+    out_node_data->AddState(ui::AX_STATE_INVISIBLE);
 
   out_node_data->location = gfx::RectF(view_->GetBoundsInScreen());
 }