Changes

# Either set the pref '''security.sandbox.logging.enabled=true''' and restart the browser OR launch the browser with the '''MOZ_SANDBOX_LOGGING''' environment variable set. Just setting the environment variable '''MOZ_SANDBOX_MAC_FLASH_LOGGING''' enables logging only for the OS X NPAPI Flash Plugin sandbox when it is enabled. * If Console.app is not already running at the time of the sandbox violation, the violation is not reliably logged.* As of build 56, where filesystem read access restrictions were tightened, running Firefox always triggers sandbox violations and these will be logged. For example, plugin-container attempts to access /Applications and /Users (bug 1378968). We want to address these when possible, but some violations are complicated to avoid or are triggered by OS X library code that can't be avoided yet.