Replace ui::AXViewState with AXNodeData and AXActionData

ui/views/view.h

 // Copyright (c) 2012 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.
 
 #ifndef UI_VIEWS_VIEW_H_
 #define UI_VIEWS_VIEW_H_
 
 #include <stddef.h>
 
 #include <algorithm>
@@ skipping 35 matching lines @@
 using ui::OSExchangeData;
 
 namespace gfx {
 class Canvas;
 class Insets;
 class Path;
 class Transform;
 }
 
 namespace ui {
-struct AXViewState;
+struct AXActionData;
+struct AXNodeData;
 class Compositor;
 class InputMethod;
 class Layer;
 class NativeTheme;
 class PaintContext;
 class TextInputClient;
 class Texture;
 class ThemeProvider;
 }
 
@@ skipping 871 matching lines @@
   // Invoked from DoDrag after the drag completes. This implementation does
   // nothing, and is intended for subclasses to do cleanup.
   virtual void OnDragDone();
 
   // Returns true if the mouse was dragged enough to start a drag operation.
   // delta_x and y are the distance the mouse was dragged.
   static bool ExceededDragThreshold(const gfx::Vector2d& delta);
 
   // Accessibility -------------------------------------------------------------
 
-  // Modifies |state| to reflect the current accessible state of this view.
-  virtual void GetAccessibleState(ui::AXViewState* state) { }
+  // Modifies |node_data| to reflect the current accessible state of this view.
+  virtual void GetAccessibleNodeData(ui::AXNodeData* node_data) {}

[sky, 2016/11/03 20:10:14]

While you're changing all this code is there a reason this function needs to
take a ui::AXNodeData rather than returning a unique_ptr<AXNodeData>? 

[dmazzoni, 2016/11/03 22:27:37]

I'm leaning against doing that because this matches the
interface elsewhere in the code, and returning
unique_ptr<AXNodeData> would add an extra copy
(in AXViewObjWrapper::Serialize). I don't see any place
where it'd save a copy. I don't think it'd make any difference
in terms of where we need to include header files.

Did you see a particular benefit of returning
unique_ptr<AXNodeData>?

I don't mind making the change, but I wanted to point out
the reasons for the current interface. Up to you.

[sky, 2016/11/03 23:12:47]

I didn't look everywhere, but in the couple of places I looked the calling code
is:

ui::AXNodeData node_data;
view->GetAccessibleNodeData(&node_data);

It seemed nicer if that is
node_data = view->GetAccessibleNodeData();

You know this code better than I though, so if you don't think it's worth it,
that makes sense. In fact looking at it again maybe it won't fly. There is code
like:

+      ui::AXNodeData node_data;
+      node_data.state = 0;
+      ime.first->GetAccessibleNodeData(&node_data);

Which won't work if you need to pass in real to GetAccessibleNodeData().

+
+  // Handle a request from assistive technology to perform an action on this
+  // view.
+  virtual void HandleAccessibleAction(const ui::AXActionData& action_data) {}

[sky, 2016/11/03 20:10:14]

Would this be easier for subclassing if it returned a boolean? I'm wondering if
doing that means subclass code could look like:

if (SuperClass::HandleAccessibleAction(action_data))
  return;

....
?

[dmazzoni, 2016/11/03 22:27:37]

Sure, done.

I added a comment to clarify that the success/failure
doesn't get communicated to the client.

 
   // Returns an instance of the native accessibility interface for this view.
   virtual gfx::NativeViewAccessible GetNativeViewAccessible();
 
   // Notifies assistive technology that an accessibility event has
   // occurred on this view, such as when the view is focused or when its
   // value changes. Pass true for |send_native_event| except for rare
   // cases where the view is a native control that's already sending a
   // native accessibility event and the duplicate event would cause
   // problems.
@@ skipping 608 matching lines @@
   // Belongs to this view, but it's reference-counted on some platforms
   // so we can't use a scoped_ptr. It's dereferenced in the destructor.
   NativeViewAccessibility* native_view_accessibility_;
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEW_H_