[Q] merging stagefright-plugins topic

I'm trying to add stagefright-plugins (https://github.com/omxcodec/stagefright-plugins) into my AOSP build. One of the instructions says
"android_frameworks_native and android_frameworks_av:
you should merge my android_frameworks_native(branch: cm_maguro-10.1) and
android_frameworks_av(branch: cm_maguro-10.1) code"
But after much searching I can't see an obvious command for repo/git that would allow me to merge those projects into the source /frameworks/ folder. Trying to manually replace/add files just results in cryptic build errors. Any help would be appreciated!