Fix the back/forward button on topbar (#3719)

* Check only webcontent type === 'window' instead of using webContents.getFocusedWebContents(), as other webview can capture focus

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>

* Update test

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>

src/renderer/components/layout/__tests__/topbar.test.tsx

@@ -50,11 +50,12 @@ const goForward = jest.fn();
 jest.mock("@electron/remote", () => {
   return {
     webContents: {
-      getFocusedWebContents: () => {
-        return {
+      getAllWebContents: () => {
+        return [{
+          getType: () => "window",
           goBack,
           goForward
-        };
+        }];
       }
     }
   };