Chapter grid snap scroll (OT-896)

[darrellcolehill]

Scrolls selected chapter to the top of the chapter grid scroll pane.

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This change is 

[darrellcolehill]

Reviewable status: 0 of 2 files reviewed, 2 unresolved discussions

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jvm/controls/src/main/kotlin/org/wycliffeassociates/otter/jvm/controls/chapterselector/ChapterGrid.kt line 47 at r1 (raw file):

    fun getSelectedChapter(): Node? {
        val selectedChapterIndex = this.list.indexOfFirst { it.selected }

Not crazy about this. I tried lookupAll(":selected).firstOrNull() but was not getting the node I needed.

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jvm/workbookapp/src/main/kotlin/org/wycliffeassociates/otter/jvm/workbookapp/ui/components/popup/ChapterSelectorPopup.kt line 82 at r1 (raw file):

    init {
        control.showingProperty().onChangeWithDisposer {

Not sure if having this in the skin is appropriate and how I would dispose of the listener.