Removing content using backspace right after paste not triggering onChange event

[Satya Minnekanti]

Steps to reproduce

1. Open nightly build . ​http://nightly.ckeditor.com/16-02-17-07-09/full/samples/
2. Open firebug or Chrome's developer tools' console tab.

3. Copy, Paste & execute following command in the console:

CKEDITOR.instances.editor.on('change', function(){ console.log('onChange triggered') })

4. Copy some text (ie. web or text editor) into clipboard using CTRL+C.

5. Go to editor body, paste copied content using CTRL+V. It will trigger the console to display "onChange triggered".

6. Now press Backspace to delete some content.

Issue : It won't trigger the onChange event to display "onChange triggered" message in console. But any Backspace after that will display the onChange message in console

[Jakub Ś]

Problem can be reproduced from CKEditor 4.4.4. Before that version, same TC produced two change events being fired for single paste and backspace (perhaps this was related to #11611).