fix expanding snippet

Author: daiyam

browser/components/CodeEditor.js

@@ -130,6 +130,7 @@ export default class CodeEditor extends React.Component {
 
   updateDefaultKeyMap () {
     const { hotkey } = this.props
+    const expandSnippet = this.expandSnippet.bind(this)
 
     this.defaultKeyMap = CodeMirror.normalizeKeyMap({
       Tab: function (cm) {
@@ -206,7 +207,6 @@ export default class CodeEditor extends React.Component {
 
   componentDidMount () {
     const { rulers, enableRulers } = this.props
-    const expandSnippet = this.expandSnippet.bind(this)
     eventEmitter.on('line:jump', this.scrollToLineHandeler)
 
     const defaultSnippet = [