Fix share tabs

The share/embed tab bar used some hacks to disable MenuSelectWidget's
normal behavior of disappearing once a selection has been made; after
the last OOUI update this doesn't work anymore.

This commit makes some small changes to make it work again:
* replace .show() with .toggle() as the widget uses a custom
  show/hide mechanism now
* reorder some calls - .toggle() has no effect as long as the menu has
  no options
* disable autoHide which would hide the menu when the user clicks
  outside (didn't test if it is really needed but seemed reasonable)

Also undoes some CSS changes that came with the update.

Bug: T89531
Change-Id: I3688ec21250bf2eb8dbfd67e306e857028d71fc7

resources/mmv/ui/mmv.ui.reuse.dialog.js

@@ -61,12 +61,10 @@
 		}
 
 		this.reuseTabs = new oo.ui.MenuSelectWidget( {
+			autoHide: false,
 			classes: [ 'mw-mmv-reuse-tabs' ]
 		} );
-
-		// MenuSelectWidget has a nasty tendency to hide itself, maybe we're not using it right?
-		this.reuseTabs.hide = $.noop;
-		this.reuseTabs.$element.show().appendTo( this.$dialog );
+		this.reuseTabs.$element.appendTo( this.$dialog );
 
 		this.tabs = {
 			share: new mw.mmv.ui.reuse.Share( this.$dialog ),
@@ -83,6 +81,10 @@
 			this.ooTabs.embed
 		] );
 
+		// MenuSelectWidget has a nasty tendency to hide itself, maybe we're not using it right?
+		this.reuseTabs.toggle( true );
+		this.reuseTabs.toggle = $.noop;
+
 		this.selectedTab = this.getLastUsedTab();
 
 		// In case nothing is saved in localStorage or it contains junk

resources/mmv/ui/mmv.ui.reuse.dialog.less

@@ -12,6 +12,8 @@
 
 		position: static;
 		box-shadow: none;
+		padding-bottom: 0; // OOUI override
+		border: none; // OOUI override
 		border-bottom: @divider-border-height solid @divider-color;
 		.box-round(@border-radius @border-radius 0 0);