Issue #2501319 by joelpittet, cwells, stefan.r, YesCT, nlisgo, Cottser, cmanalansan, dawehner, xjm, alexpott, josephdpurcell: Remove SafeMarkup::set() in Error::renderExceptionSafe() and _drupal_log_error() and improve backtrace formatting consistency in _drupal_log_error(), Error::renderExceptionSafe(), and DefaultExceptionSubscriber::onHtml()

Issue #2540438 by znerol, timmillwood: Invalid format string when falling back to error_log in _drupal_log_error()

Issue #2509898 by dawehner, znerol, larowlan, lauriii, Aki Tendo, Wim Leers: Additional uncaught exception thrown while handling exception after service changes