[sql lab] ctrl-r hotkey should run latest SQL (#4719)

Turns out the SQL would only be committed to the redux store `onBlur`
event to avoid the laggy typing. The delay come from the localStorage
binding that add enough millisecs of delay to feel odd while typing.

I now store the most recent SQL in the local and use that instead.

superset/assets/javascripts/SqlLab/components/AceEditorWrapper.jsx

@@ -37,10 +37,12 @@ const propTypes = {
     descr: PropTypes.string.isRequired,
     func: PropTypes.func.isRequired,
   })),
+  onChange: PropTypes.func,
 };
 
 const defaultProps = {
   onBlur: () => {},
+  onChange: () => {},
   tables: [],
 };
 
@@ -51,6 +53,7 @@ class AceEditorWrapper extends React.PureComponent {
       sql: props.sql,
       selectedText: '',
     };
+    this.onChange = this.onChange.bind(this);
   }
   componentDidMount() {
     // Making sure no text is selected from previous mount
@@ -97,6 +100,10 @@ class AceEditorWrapper extends React.PureComponent {
       }
     });
   }
+  onChange(text) {
+    this.setState({ sql: text });
+    this.props.onChange(text);
+  }
   getCompletions(aceEditor, session, pos, prefix, callback) {
     callback(null, this.state.words);
   }
@@ -125,9 +132,6 @@ class AceEditorWrapper extends React.PureComponent {
       }
     });
   }
-  textChange(text) {
-    this.setState({ sql: text });
-  }
   render() {
     return (
       <AceEditor
@@ -136,7 +140,7 @@ class AceEditorWrapper extends React.PureComponent {
         onLoad={this.onEditorLoad.bind(this)}
         onBlur={this.onBlur.bind(this)}
         height={this.props.height}
-        onChange={this.textChange.bind(this)}
+        onChange={this.onChange}
         width="100%"
         editorProps={{ $blockScrolling: true }}
         enableLiveAutocompletion