Slider: Modified to allow value to reach max value with float step

Fixes #11286
Closes gh-1465
(cherry picked from commit 60c00cd)

tests/unit/slider/slider_methods.js

@@ -62,7 +62,7 @@ test( "disable", function() {
 });
 
 test( "value", function() {
-	expect( 17 );
+	expect( 18 );
 	$( [ false, "min", "max" ] ).each(function() {
 		var element = $( "<div></div>" ).slider({
 			range: this,
@@ -88,6 +88,16 @@ test( "value", function() {
 	equal( element.slider( "value" ), 1, "value method get respects max" );
 	equal( element.slider( "value", 2 ), element, "value method is chainable" );
 	equal( element.slider( "option", "value" ), 1, "value method set respects max" );
+
+	// set max value with step 0.01
+	element.slider( "option", {
+		min: 2,
+		value: 2,
+		max: 2.4,
+		step: 0.01
+	});
+	element.slider( "option", "value", 2.4 );
+	equal( element.slider( "value" ), 2.4, "value is set to max with 0.01 step" );
 });
 
 //test( "values", function() {

ui/slider.js

@@ -550,7 +550,7 @@ return $.widget( "ui.slider", $.ui.mouse, {
 		var max = this.options.max,
 			min = this._valueMin(),
 			step = this.options.step,
-			aboveMin = Math.floor( ( max - min ) / step ) * step;
+			aboveMin = Math.floor( ( +( max - min ).toFixed( this._precision() ) ) / step ) * step;
 		max = aboveMin + min;
 		this.max = parseFloat( max.toFixed( this._precision() ) );
 	},