fix weird NPE with calling webContents.isDevToolsFocused

src/vs/workbench/electron-main/menus.ts

@@ -654,7 +654,7 @@ export class VSCodeMenu {
 					return;
 				}
 
-				if (windowInFocus.win.webContents.isDevToolsFocused()) {
+				if (windowInFocus.win.webContents.isDevToolsFocused && windowInFocus.win.webContents.isDevToolsFocused()) { // timing issue, sometimes isDevToolsFocused is not defined?
 					devToolsFocusedFn(windowInFocus.win.devToolsWebContents);
 				} else {
 					windows.manager.sendToFocused('vscode:runAction', actionId);