Ref #14313: NaN detection. Close gh-1352.

(cherry picked from commit 0bc0a690)

src/core.js

@@ -221,7 +221,10 @@ jQuery.extend({
 	},
 
 	isNumeric: function( obj ) {
-		return !isNaN( parseFloat(obj) ) && isFinite( obj );
+		// parseFloat NaNs numeric-cast false positives (null|true|false|"")
+		// ...but misinterprets leading-number strings, particularly hex literals ("0x...")
+		// subtraction forces infinities to NaN
+		return obj - parseFloat( obj ) >= 0;
 	},
 
 	type: function( obj ) {

src/css.js

@@ -273,8 +273,8 @@ jQuery.extend({
 				type = "number";
 			}
 
-			// Make sure that NaN and null values aren't set. See: #7116
-			if ( value == null || type === "number" && isNaN( value ) ) {
+			// Make sure that null and NaN values aren't set. See: #7116
+			if ( value == null || value !== value ) {
 				return;
 			}