fixup! fix($compile): fix ng-prop-* with undefined values

Author: jbedard

src/ng/compile.js

@@ -3836,7 +3836,8 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
           return {
             pre: function ngPropPreLinkFn(scope, $element) {
               function applyPropValue() {
-                $element[0][propName] = sanitizer(ngPropGetter(scope));
+                var propValue = ngPropGetter(scope);
+                $element[0][propName] = sanitizer(propValue);
               }
 
               applyPropValue();