Fix lost index on selection change in Attribute Table

[signedav]

Issue was that the index always jumps to the first position when I make a feature selection (yellow):

IndexLostOnSelection.webm

The original implementation intended that the index jumps to the first feature in the made selection (in case the indexed feature is currently not in the selection - otherwise the index should presist). But this did not work: Problem was that when the connection to the lambda updating the index has the parameter of it's initialization. Means inSelection was always false and with this the index received 0 (first position).

This fix decapsulates the update function from where the timer to trigger starts. Since we cannot pass the parameter inSelection because of the timer I created two timer (and with it two connections).

I decided against a quick fix with deconnect/connect the lambda function on every ensureEditSelection because of the fragility of those triggers in the attribute table. The proposed sollution is in my opinion more secure.

Fixed sollution looks like this:

selectiontakesindex.webm

[m-kuhn]

Thank you!