Two tests have flaky crashes:

compositing/overflow/do-not-paint-outline-into-composited-scrolling-contents.html
virtual/prefer_compositing_to_lcd_text/compositing/overflow/do-not-paint-outline-into-composited-scrolling-contents.html

Stack trace:

STDERR: [1:1:0308/131122.789608:1018318194454:FATAL:SimplifiedBackwardsTextIterator.cpp(145)] Check failed: m_positionNode. 
STDERR: #0 0x7fe78fe29bbb base::debug::StackTrace::StackTrace()
STDERR: #1 0x7fe78fe2824c base::debug::StackTrace::StackTrace()
STDERR: #2 0x7fe78fe9673f logging::LogMessage::~LogMessage()
STDERR: #3 0x7fe7864346ba blink::SimplifiedBackwardsTextIteratorAlgorithm<>::advance()
STDERR: #4 0x7fe78642a274 blink::BackwardsCharacterIteratorAlgorithm<>::advance()
STDERR: #5 0x7fe78646c15e blink::(anonymous namespace)::calculateHotModeCheckingRange()
STDERR: #6 0x7fe78646bf36 blink::HotModeSpellCheckRequester::checkSpellingAt()
STDERR: #7 0x7fe78646e29a blink::IdleSpellCheckCallback::hotModeInvocation()
STDERR: #8 0x7fe78646ee4f blink::IdleSpellCheckCallback::handleEvent()
STDERR: #9 0x7fe7862879b4 blink::ScriptedIdleTaskController::runCallback()
STDERR: #10 0x7fe786287567 blink::ScriptedIdleTaskController::callbackFired()
STDERR: #11 0x7fe7862884cd blink::internal::IdleRequestCallbackWrapper::timeoutFired()