IE: editor blinks and Drop-downs closed immediately after show when CKEditor opened as a modal dialog

[Irina]

Steps to reproduce:

1. Copy ckeditor_test.html and blink.html to some HTTP server(not reproducible on local).
2. Open blink.html and click show modal dialog button.
3. Click on "Font" drop-down, don't close it, click "Size" drop-down

Problems:

The screen will blink when modal dialog opens. Clicking on other drop-downs ("Font", "Size", "Format") will show and immediate hide them and screen will blink each time.

Browser: IE9/10/11

[Irina]

Another way to reproduce this issue:

1. Open blink.html and click show modal dialog button.
2. Create a table
3. Right click to get the table context menu
4. Move the cursor to the 'cell' menu option

Problem: Context menu disappears and we can't select any option from the menu.

[Irina]

The screencast for the table context menu problem

[Jakub Ś]

We have got few similar issues with modal dialog: #9934, #7078, #8137 and #7175.

This issue is a duplicate of #7175.