Fix the B2G viewer and enable bot preview.
Fix bot breakage caused by Chromium extension PR
Merge pull request #3794 from brendandahl/b2g-fix

Fix the B2G viewer and enable bot preview.
Merge pull request #3822 from Snuffleupagus/fix-chromium-PR-bot-breakage

Fix bot breakage caused by Chromium extension PR
Merge branch 'master' of git://github.com/mozilla/pdf.js into secondary-toolbar-elements
Better names