this scripts installs: Flash, PDF, for some Chromium OS builds. (confirmed on Vanilla build 3389 Built on 12th December 2012!) Carputers confirmed that it also works on ArnoldTheBat's Cx86OS-20130423010101 build!
Sadly enough the Hangouts stopped working! i don't know about Netflix, since i can't test it. and since ~4-08-2013 MP3/Mp4 stopped working?
if you want to use this script on ArnoldTheBat's Chromium OS build, keep in mind that he uses the password: "password" instead of "facepunch". (without the quotes ;))