fix form entry within scrolllock

lib/ScrollLock.js

@@ -111,6 +111,10 @@ var ScrollLock = function (_Component) {
     }, {
         key: 'onKeyDownHandler',
         value: function onKeyDownHandler(e) {
+            if (e.target !== this.scrollingElement) {
+                return;
+            }
+
             if (upKeys.indexOf(e.keyCode) >= 0) {
                 this.handleEventDelta(e, -1);
             } else if (downKeys.indexOf(e.keyCode) >= 0) {

src/ScrollLock.jsx

@@ -95,6 +95,10 @@ export default class ScrollLock extends Component {
     }
 
     onKeyDownHandler(e) {
+        if (e.target !== this.scrollingElement) {
+            return;
+        }
+
         if (upKeys.indexOf(e.keyCode) >= 0) {
             this.handleEventDelta(e, -1);
         } else if (downKeys.indexOf(e.keyCode) >= 0) {

test/ScrollLock.test.jsx

@@ -128,6 +128,10 @@ describe('ScrollLock', () => {
                 component = scrollLockInstance();
                 component.handleEventDelta = jest.fn();
             });
+            it('should not call handleEventDelta if keydown target is not the scrolling element', () => {
+                component.onKeyDownHandler({ keyCode: 32, target: <input /> });
+                expect(component.handleEventDelta).toHaveBeenCalledTimes(0);
+            });
             it('should call handleEventDelta with delta of 1 for space bar', () => {
                 const synthEvent = { keyCode: 32 };
                 component.onKeyDownHandler(synthEvent);