There's a check in the installer for display_errors which gives a warning if it's turned on. Even if it's turned off in php.ini it'll still show up this warning because this line of code makes the check useless:
Suggested fix is to check the original value before display_errors is set to "On" by the installer.
Hah yeah that's a doozie - we should check the original value. Pull request? ;)
I'll take care of this.
BUG Fixing installer not checking display_errors correctly.
Fixes issue #2479. Installer sets display_errors on, but it checks
the changed value and not the original one set in php.ini.