IE6-8 selection range lost when pasting with dialog

[Jakub Ś]

I have found it when checking #8849.

To reproduce:

1. Load the "replacebyclass" sample;
2. Select first line and copy/paste it. You should have 7 lines.
3. Select the bold text "sample text" in third line from the bottom;
4. Press Tab key to move focus outside of editor;
5. Click on "Paste" toolbar button, choose to deny clipboard access in order to bring up dialog.
6. Fill in the dialog with some text "abc" then click on Ok

Result: Selection is applied to wrong text.

1. This particular issue has been reproducible from rev. [7518]
2. Before this rev. the above TC produced JS error:

Message: Invalid argument.
Line: 802
URI: /ckeditor/_source/plugins/selection/plugin.js
It has been reproducible from rev. [7239] to [7883]; got fixed and showed up again from [7447] to [7517]