Implement GetParent, GetChildCount, ChildAtIndex on BrowserAccessibility

content/browser/accessibility/browser_accessibility.cc

 // 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.
 
 #include "content/browser/accessibility/browser_accessibility.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <iterator>
@@ skipping 1116 matching lines @@
         bounds.Offset(-sx, -sy);
       }
     }
 
     node = container;
   }
 
   return gfx::ToEnclosingRect(bounds);
 }
 
 // AXPlatformNodeDelegate.

[dmazzoni, 2017/04/21 16:22:27]

nit: make this a larger block comment like we have in
browser_accessibility_win:

//
// AXPlatformNodeDelegate.
//

 const ui::AXNodeData& BrowserAccessibility::GetData() const {
   CR_DEFINE_STATIC_LOCAL(ui::AXNodeData, empty_data, ());
   if (node_)
     return node_->data();
   else
     return empty_data;
 }
 
 gfx::NativeWindow BrowserAccessibility::GetTopLevelWidget() {
   NOTREACHED();
   return nullptr;
 }
 
 gfx::NativeViewAccessible BrowserAccessibility::GetParent() {
-  NOTREACHED();
+  auto* parent = PlatformGetParent();
+  if (parent && parent->platform_node_)
+    return parent->platform_node_->GetNativeViewAccessible();
   return nullptr;
 }
 
 int BrowserAccessibility::GetChildCount() {
-  NOTREACHED();
-  return -1;
+  return PlatformChildCount();
 }
 
 gfx::NativeViewAccessible BrowserAccessibility::ChildAtIndex(int index) {
-  NOTREACHED();
+  auto* child = PlatformGetChild(index);
+  if (child && child->platform_node_)
+    return child->platform_node_->GetNativeViewAccessible();
   return nullptr;
 }
 
 gfx::Rect BrowserAccessibility::GetScreenBoundsRect() const {
   gfx::Rect bounds = GetPageBoundsRect();
 
   // Adjust the bounds by the top left corner of the containing view's bounds
   // in screen coordinates.
   bounds.Offset(manager_->GetViewBounds().OffsetFromOrigin());
 
@@ skipping 16 matching lines @@
   return gfx::kNullAcceleratedWidget;
 }
 
 bool BrowserAccessibility::AccessibilityPerformAction(
     const ui::AXActionData& data) {
   NOTREACHED();
   return false;
 }
 
 }  // namespace content