Correctly finds line boundaries in objects with rich text on Windows.

content/renderer/accessibility/blink_ax_tree_source.cc

Index: content/renderer/accessibility/blink_ax_tree_source.cc
diff --git a/content/renderer/accessibility/blink_ax_tree_source.cc b/content/renderer/accessibility/blink_ax_tree_source.cc
index ac907ab1f406e9439be257da27e283e4c71f01e8..098c74726e59457b6c55c27451b8fb03c18e1c65 100644
--- a/content/renderer/accessibility/blink_ax_tree_source.cc
+++ b/content/renderer/accessibility/blink_ax_tree_source.cc
@@ -403,6 +403,19 @@ void BlinkAXTreeSource::SerializeNode(blink::WebAXObject src,
         src.keyboardShortcut().utf8());
   }
 
+  if (dst->role == ui::AX_ROLE_STATIC_TEXT ||

[dmazzoni, 2016/04/22 21:43:38]

It wasn't my intent for "next on line" and "previous on line" to only be
supported for those roles. I think it can be quite helpful for other roles too.

As an example, suppose you have an inline image:

<p>Before <img src="graphic.png" alt="graphic"> After</p>

You should be able to use nextOnLine and previousOnLine to trace from the word
Before to the inline image, to the word After, if they all happen to be laid out
on the same line.

+      dst->role == ui::AX_ROLE_LINE_BREAK ||
+      dst->role == ui::AX_ROLE_INLINE_TEXT_BOX) {
+    if (!src.nextOnLine().isDetached())
+      dst->AddIntAttribute(ui::AX_ATTR_NEXT_ON_LINE_ID,
+                           src.nextOnLine().axID());
+
+    if (!src.previousOnLine().isDetached()) {
+      dst->AddIntAttribute(ui::AX_ATTR_PREVIOUS_ON_LINE_ID,
+                           src.previousOnLine().axID());
+    }
+  }
+
   if (!src.ariaActiveDescendant().isDetached()) {
     dst->AddIntAttribute(ui::AX_ATTR_ACTIVEDESCENDANT_ID,
                          src.ariaActiveDescendant().axID());