Tooltip: Fix re-enabling of delegated tooltips

Fixes #14950
Closes gh-1699

tests/unit/tooltip/methods.js

@@ -94,6 +94,20 @@ QUnit.test( "enable/disable", function( assert ) {
	$.fx.off = false;
} );

QUnit.test( "enable/disable delegated", function( assert ) {
	assert.expect( 1 );
	var element = $( "#qunit-fixture" ).tooltip();
	var tooltipped = $( "#tooltipped1" );

	element.tooltip( "disable" );
	element.tooltip( "enable" );

	tooltipped.trigger( "mouseover" );
	assert.equal( $( ".ui-tooltip" ).length, 1, "open" );

	element.tooltip( "destroy" );
} );

QUnit.test( "widget", function( assert ) {
	assert.expect( 2 );
	var element = $( "#tooltipped1" ).tooltip(),

ui/widgets/tooltip.js

@@ -114,6 +114,8 @@ $.widget( "ui.tooltip", {
			} )
			.appendTo( this.document[ 0 ].body );
		this._addClass( this.liveRegion, null, "ui-helper-hidden-accessible" );

		this.disabledTitles = $( [] );
	},

	_setOption: function( key, value ) {
@@ -143,25 +145,29 @@ $.widget( "ui.tooltip", {
		} );

		// Remove title attributes to prevent native tooltips
		this.element.find( this.options.items ).addBack().each( function() {
			var element = $( this );
			if ( element.is( "[title]" ) ) {
				element
					.data( "ui-tooltip-title", element.attr( "title" ) )
					.removeAttr( "title" );
			}
		} );
		this.disabledTitles = this.disabledTitles.add(
			this.element.find( this.options.items ).addBack()
				.filter( function() {
					var element = $( this );
					if ( element.is( "[title]" ) ) {
						return element
							.data( "ui-tooltip-title", element.attr( "title" ) )
							.removeAttr( "title" );
					}
				} )
		);
	},

	_enable: function() {

		// restore title attributes
		this.element.find( this.options.items ).addBack().each( function() {
		this.disabledTitles.each( function() {
			var element = $( this );
			if ( element.data( "ui-tooltip-title" ) ) {
				element.attr( "title", element.data( "ui-tooltip-title" ) );
			}
		} );
		this.disabledTitles = $( [] );
	},

	open: function( event ) {