create_release.py: Push resulting branch to origin

[sbc100]

Also, set the upstream when creating the new branch.

See emscripten-core/emsdk#1255

[dschuff]

ah, so I just realized that I use the emscripten repo inside an emscripten-releases checkout. this means its 'origin' is actually chromium.googlesource.com/emscripten rather than github (I just have another remote to push to github). So this won't work for me.
One option would be to make this overridable via an env var or something. but let me also check whether gclient still works if I rename my origin remote.

[sbc100]

ah, so I just realized that I use the emscripten repo inside an emscripten-releases checkout. this means its 'origin' is actually chromium.googlesource.com/emscripten rather than github (I just have another remote to push to github). So this won't work for me. One option would be to make this overridable via an env var or something. but let me also check whether gclient still works if I rename my origin remote.

Yes, maybe see if you can set github as your origin. Failing that we can add a flag I guess? Or check the origin URL?

[dschuff]

OK, yeah gclient sync seems to work fine with the github remote as 'origin'.