Position: Remove fractional pixel detection

Hooray for newer browsers.

Closes gh-1739

ui/position.js

@@ -27,10 +27,9 @@
 	}
 }( function( $ ) {
 ( function() {
-var cachedScrollbarWidth, supportsOffsetFractions,
+var cachedScrollbarWidth,
 	max = Math.max,
 	abs = Math.abs,
-	round = Math.round,
 	rhorizontal = /left|center|right/,
 	rvertical = /top|center|bottom/,
 	roffset = /[\+\-]\d+(\.[\d]+)?%?/,
@@ -38,26 +37,6 @@ var cachedScrollbarWidth, supportsOffsetFractions,
 	rpercent = /%$/,
 	_position = $.fn.position;
 
-// Support: IE <=9 only
-supportsOffsetFractions = function() {
-	var element = $( "<div>" )
-			.css( "position", "absolute" )
-			.appendTo( "body" )
-			.offset( {
-				top: 1.5,
-				left: 1.5
-			} ),
-		support = element.offset().top === 1.5;
-
-	element.remove();
-
-	supportsOffsetFractions = function() {
-		return support;
-	};
-
-	return support;
-};
-
 function getOffsets( offsets, width, height ) {
 	return [
 		parseFloat( offsets[ 0 ] ) * ( rpercent.test( offsets[ 0 ] ) ? width / 100 : 1 ),
@@ -266,12 +245,6 @@ $.fn.position = function( options ) {
 		position.left += myOffset[ 0 ];
 		position.top += myOffset[ 1 ];
 
-		// If the browser doesn't support fractions, then round for consistent results
-		if ( !supportsOffsetFractions() ) {
-			position.left = round( position.left );
-			position.top = round( position.top );
-		}
-
 		collisionPosition = {
 			marginLeft: marginLeft,
 			marginTop: marginTop