restore b2g agent sheet scrollbars on b2g windows (based on FloatingScrollbars module from devtools)
Merge branch 'fix-inject-b2g-stylesheet' of git://github.com/rpl/r2d2b2g into rpl-fix-inject-b2g-stylesheet
reinject b2g mobile agent stylesheet from a "content-document-global-created" notification observer
inject into the FirefoxOS iframe container to fix style issues on app switcher and mobile select
minor tweaks on prothesis window-manager.js
Merge branch 'fix-inject-b2g-stylesheet' of git://github.com/rpl/r2d2b2g into rpl-fix-inject-b2g-stylesheet
prevents b2g stylsheet inject side-effect on running an app during b2g startup

- move b2g stylesheet injection code into its own file (inject-b2g-agentsheet.js)
- observe "content-document-global-created" notification before ContentStart to
  inject into "iframe#homescreen" created inside shell.xul
  (prevents layouting bug on running app during b2g startup)
Merge branch 'fix-inject-b2g-stylesheet' of git://github.com/rpl/r2d2b2g into rpl-fix-inject-b2g-stylesheet
add license header; fix code style nit
Merge branch 'rpl-fix-inject-b2g-stylesheet'