electron libchromium build 3.0.13

I am building electron from source in windows, i am particularly interested in changing some webrtc module codes in release mode.

i have build electron from source, and trying to change chromium.

this link is about chromium development - https://github.com/electron/electron/blob/v3.0.13/docs/development/chromium-development.md after i changed code i could build only in debug mode and my changes reflect. But there is no clear way to build in release mode.
thank you…