handle common flash install locations for Linux
handle common flash install locations for Linux

I think this can be reverted once https://cs.chromium.org/chromium/src/chrome/common/chrome_paths.cc?sq=package:chromium&dr=C&rcl=1469791693&l=304 is fixed.

Fix #2784

Auditors: 3b7c71ee0e5cc446e346f75e333ddae4d394475d@alexwykoff

darkdh/browser-laptop,dcposch/browser-laptop,MKuenzi/browser-laptop,timborden/browser-laptop,luixxiul/browser-laptop,luixxiul/browser-laptop,MKuenzi/browser-laptop,Sh1d0w/browser-laptop,timborden/browser-laptop,diasdavid/browser-laptop,manninglucas/browser-laptop,timborden/browser-laptop,manninglucas/browser-laptop,willy-b/browser-laptop,dcposch/browser-laptop,willy-b/browser-laptop,pmkary/braver,jonathansampson/browser-laptop,Sh1d0w/browser-laptop,pmkary/braver,dcposch/browser-laptop,jonathansampson/browser-laptop,jonathansampson/browser-laptop,darkdh/browser-laptop,luixxiul/browser-laptop,Sh1d0w/browser-laptop,luixxiul/browser-laptop,willy-b/browser-laptop,jonathansampson/browser-laptop,darkdh/browser-laptop,manninglucas/browser-laptop,manninglucas/browser-laptop,timborden/browser-laptop,Sh1d0w/browser-laptop,pmkary/braver,MKuenzi/browser-laptop,diasdavid/browser-laptop,pmkary/braver,diasdavid/browser-laptop,willy-b/browser-laptop,MKuenzi/browser-laptop,diasdavid/browser-laptop,dcposch/browser-laptop,darkdh/browser-laptop