Created attachment 278164 [details]
accessible-event listener

Steps to reproduce:
1. Launch one of gtk3-demo's Entry demos
2. Launch the attached accessible-event listener in a terminal
3. In the entry type "ab"
4. Press Home to move to the beginning, then type "cd"

Expected results: The newly-inserted character would be provided as the accessible event's any_data (see below for output).

Actual results: Whatever character (if any) is at the insertion point is provided as the accessible event's any_data (see below for output).

Notes: 
1. This is a regression, but I've gone back and it is present in at least 3.8.0. Not sure when it was introduced wrt Gtk+ 3. But it is not present in Gtk+ 2.

2. This issue is not present for GtkTextView; just GtkEntry.

Expected results / Gtk+ 2 results:
==================================
object:text-changed:insert(0, 1, a)
	source: [text | ]
	host_application: [application | gtk-demo]
object:text-changed:insert(1, 1, b)
	source: [text | ]
	host_application: [application | gtk-demo]
object:text-changed:insert(0, 1, c)
	source: [text | ]
	host_application: [application | gtk-demo]
object:text-changed:insert(1, 1, d)
	source: [text | ]
	host_application: [application | gtk-demo]


Actual results / Gtk+ 3 results:
================================
object:text-changed:insert(0, 1, ) <-- "a" missing
	source: [text | ]
	host_application: [application | gtk3-demo]
object:text-changed:insert(1, 1, ) <-- "b" missing
	source: [text | ]
	host_application: [application | gtk3-demo]
object:text-changed:insert(0, 1, a) <-- should be "c"; not "a"
	source: [text | ]
	host_application: [application | gtk3-demo]
object:text-changed:insert(1, 1, a) <-- should be "d"; not "a"
	source: [text | ]
	host_application: [application | gtk3-demo]