Implement automatic load of composed/embedded automation trees

ui/accessibility/ax_enums.idl

Index: ui/accessibility/ax_enums.idl
diff --git a/ui/accessibility/ax_enums.idl b/ui/accessibility/ax_enums.idl
index 5add7a4227431400d49a77c19fc65f15665eb092..be09a5d97029cd1939cab33cc37c85d6e6232f89 100644
--- a/ui/accessibility/ax_enums.idl
+++ b/ui/accessibility/ax_enums.idl
@@ -294,7 +294,12 @@
     color_value_blue,
 
     // Inline text attributes.
-    text_direction
+    text_direction,
+
+    // Internal only; do not expose to platform APIs.

[dmazzoni, 2014/10/29 06:53:30]

I don't think we should put these here.

Let's add ax_frame_id that specifies the frame id of an axtree, and
ax_child_frame_id that specifies the id of a child axtree contained within this
tree.

[aboxhall, 2014/10/29 19:29:11]

I'm confused by this. These are being now used as process_id and routing_id but
not named as such. Was that what you intended?

[David Tseng, 2014/10/29 20:35:30]

It is; the intent is to have us ultimately use abstracted frame/child frame id's
which we as accessibility keep track of. Added TODO.

[aboxhall, 2014/10/29 20:53:29]

I find this really confusing. Why not just put process_id and routing_id in here
while we're still using them? (This question as much for Dominic.)

+    // Only applicable to views::WebView.
+    process_id,
+    routing_id
   };
 
   [cpp_enum_prefix_override="ax_attr"] enum AXFloatAttribute {