Autocomplete: Don't reset text field value on blur unless it will act…

…ually change the value. Fixes #5900 - Autocomplete: mousing over menu option replaces text box contents, moves caret.

ui/jquery.ui.autocomplete.js

@@ -153,7 +153,10 @@ $.widget( "ui.autocomplete", {
 					self.selectedItem = item;
 				},
 				blur: function( event, ui ) {
-					if ( self.menu.element.is(":visible") ) {
+					// don't set the value of the text field if it's already correct
+					// this prevents moving the cursor unnecessarily
+					if ( self.menu.element.is(":visible") &&
+						( self.element.val() !== self.term ) ) {
 						self.element.val( self.term );
 					}
 				}