[PATCH] Pressing Delete when nothing is selected throws a warning

[AlThePhoenix]

Related to #2971

Start a game and the first thing you do is pressing delete.

WARNING: JavaScript warning: __internal(32) press line 0 reference to undefined property g_Selection.toList(...)[0]

[AlThePhoenix]

Basically the exact same patch used in #2971. Credit goes to leper.

[AlThePhoenix]

Different approach using only one line, credit goes to elexis. Changes the fix for #2971 as well for uniformity.

[mimo]

In fact, toList creates a temporary array from the selection object. That's a waste of resources (even if very small) when we are only interested in the first entry. So a more cleaner fix could be to add a new function getFirstSelected in selection.js which would return either the first entry (using toList way) or undefined if none. Iirc there are also a few other places in the gui where such a function could be used (when we only need the first selected or just want to be sure the selection is not empty).

[AlThePhoenix]

Created a new function in selection.js which returns the first entity in the selection. Adjusted camera.xml and misc.xml accordingly.

[mimo]

In 17114:

fix JS undefined property warning, patch by Evulant (AlThePhoenix), fixes #3496

[mimo]

Thanks for the patch