Inner duplicated style is not being removed

[Frederico Caldeira Knabben]

Using CKEDITOR.style.applyToRange to re-apply styles is not cleaning up inner duplicated styles.

For example, when applying the <b> style on the following selection:

<b>this [is</b> some] sample text

Results on this:

<b>this <b>is</b> some</b> sample text

While the expected is this:

<b>this is some</b> sample text

I'll add a TC for this.

[Frederico Caldeira Knabben]

TC added to t/8252:
​http://ckeditor.t/dt/plugins/styles/styles.html

[Jakub Ś]

Reproducible form CKE 3.4.2