Fixing issue with keyboard navigation

Author: mzabriskie

lib/tabs.js

@@ -99,11 +99,14 @@ module.exports = React.createClass({
 handleKeyDown: function (e) {
 if (isTabNode(e.target)) {
 var index = this.getSelectedIndex(),
-max = this.getTabs().length - 1;
+max = this.getTabs().length - 1,
+preventDefault = false;
 
 // Select next tab to the left
 if (e.keyCode === 37 || e.keyCode === 38) {
 index -= 1;
+preventDefault = true;
+
 // Wrap back to last tab if index is negative
 if (index < 0) {
 index = max;
@@ -112,12 +115,19 @@ module.exports = React.createClass({
 // Select next tab to the right
 else if (e.keyCode === 39 || e.keyCode === 40) {
 index += 1;
+preventDefault = true;
+
 // Wrap back to first tab if index exceeds max
 if (index > max) {
 index = 0;
 }
 }
 
+// This prevents scrollbars from moving around
+if (preventDefault) {
+e.preventDefault();
+}
+
 this.setSelected(index, true);
 }
 },