Progress toward #2389 and #2390.  This puts the right options in the menu based on whether a sprite or the stage is selected. It does not update the currently selected options menu item when you change the sprite selector menu yet though.

* Override blocks playNote_ to emit VM event

* update blocks

* Handle recordSoundCallback from blocks

* Set custom field type for sounds menu

* Add record… item to sounds menu

* Use localized string and ID for ‘record…’ option

* Add integration test

* Don’t use custom field for sounds menu

* Use callback as the value of the ‘record…’ menu item

Using the new `ScratchMsgs.translate` function to generate localized menus and default values in the toolbox.

This reverts commit 94915a9a.

* Update blocks.js