Slow BrowerWindow because of slow Menu

[jrieken]

• Electron version: 1.7.x
• Operating system: all

Expected behavior

calling new BrowserWindows should not spend 30-300ms creating Menu

Actual behavior

We get reports from our users, via code --prof-start, that show that creating a new browser windows is often slow. The profiles all point to the Menu constructor which ideally takes around 30ms but often takes more than 250ms (microsoft/vscode#21964)

Ideally this can be avoided, esp. because this builds the default menu not the actual menu.

To repro

• get VS Code, start with code --prof-startup,
• inspect the main-profile using node-inspector,

or

• clone https://github.com/jrieken/electron-quick-start,
• run the npm run start-perf script, which breaks on port 5678
• attach dev tools and profile..

[codebytere]

We are no longer implementing bugfixes for versions of Electron < 1.8.x, so i'm going to close this issue but if it is still persisting in more recent versions of Electron we can certainly reopen it!