correct misleading content about render function (#552)

* add usage that pass setup function to defineComponent

* correct misleading content about render function

src/guide/render-function.md

@@ -296,26 +296,16 @@ render() {
 
 #### Event Modifiers
 
-For the `.passive`, `.capture`, and `.once` event modifiers, Vue offers object syntax of the handler:
+For the `.passive`, `.capture`, and `.once` event modifiers, they can be concatenated after event name using camel case.
 
 For example:
 
 ```javascript
 render() {
   return Vue.h('input', {
-    onClick: {
-      handler: this.doThisInCapturingMode,
-      capture: true
-    },
-    onKeyup: {
-      handler: this.doThisOnce,
-      once: true
-    },
-    onMouseover: {
-      handler: this.doThisOnceInCapturingMode,
-      once: true,
-      capture: true
-    },
+    onClickCapture: this.doThisInCapturingMode,
+    onKeyupOnce: this.doThisOnce,
+    onMouseoverOnceCapture: this.doThisOnceInCapturingMode,
   })
 }
 ```