The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/886c47e07620987f5dbe8c2824e45b82de17433a

commit 886c47e07620987f5dbe8c2824e45b82de17433a
Author: tapted <tapted@chromium.org>
Date: Mon Aug 01 03:41:53 2016

Mark LayoutTest updating-scrolling-container-and-content as FLAKY

BUG= 633026 , 619103
TBR=wangxianzhu@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2194123002
Cr-Commit-Position: refs/heads/master@{#408906}

[modify] https://crrev.com/886c47e07620987f5dbe8c2824e45b82de17433a/third_party/WebKit/LayoutTests/TestExpectations

From https://storage.googleapis.com/chromium-layout-test-archives/WebKit_Win7__dbg_/6711/layout-test-results/results.html

Hits this NOTREACHED it seems

void PaintController::checkUnderInvalidation()
{
    DCHECK(RuntimeEnabledFeatures::slimmingPaintUnderInvalidationCheckingEnabled());

    if (!isCheckingUnderInvalidation())
        return;

    const DisplayItem& newItem = m_newDisplayItemList.last();
    size_t oldItemIndex = m_underInvalidationCheckingBegin + m_skippedProbableUnderInvalidationCount;
    const DisplayItem* oldItem = oldItemIndex < m_currentPaintArtifact.getDisplayItemList().size() ? &m_currentPaintArtifact.getDisplayItemList()[oldItemIndex] : nullptr;

    if (newItem.isCacheable() && !clientCacheIsValid(newItem.client())) {
        showUnderInvalidationError("under-invalidation of PaintLayer: invalidated in cached subsequence", newItem, oldItem);
        NOTREACHED();
    }


output like

STDERR: [4884:5124:0731/210252:3916561:FATAL:paintcontroller.cpp(554)] Check failed: false. 
STDERR: Backtrace:
STDERR: 	base::debug::StackTrace::StackTrace [0x01B45BD7+23]
STDERR: 	logging::LogMessage::~LogMessage [0x01B9386B+59]
STDERR: 	blink::PaintController::checkUnderInvalidation [0x07B849A9+441]
STDERR: 	blink::PaintController::processNewItem [0x07B87B68+1144]
STDERR: 	blink::PaintController::createAndAppend<blink::DrawingDisplayItem,blink::DisplayItemClient const &,enum blink::DisplayItem::Type const &,WTF::PassRefPtr<SkPicture>,bool &> [0x07B72B50+112]
STDERR: 	blink::DrawingRecorder::~DrawingRecorder [0x07B72FBE+302]
STDERR: 	blink::DrawingRecorder::`scalar deleting destructor' [0x157A15D0+16]
STDERR: 	base::internal::OptionalStorage<blink::DrawingRecorder,0>::~OptionalStorage<blink::DrawingRecorder,0> [0x157A0F25+37]
STDERR: 	base::Optional<blink::DrawingRecorder>::~Optional<blink::DrawingRecorder> [0x157A0E4F+15]
STDERR: 	blink::LayoutObjectDrawingRecorder::~LayoutObjectDrawingRecorder [0x157A1052+18]
STDERR: 	blink::BoxPainter::paintBoxDecorationBackgroundWithRect [0x157AE5F6+742]
STDERR: 	blink::BoxPainter::paintBoxDecorationBackground [0x157AE308+56]
STDERR: 	blink::LayoutBox::paintBoxDecorationBackground [0x15915444+36]
STDERR: 	blink::BlockPainter::paintObject [0x157A25A9+137]
STDERR: 	blink::LayoutBlock::paintObject [0x158DF324+36]
STDERR: 	blink::BlockPainter::paint [0x157A2063+243]
STDERR: 	blink::LayoutBlock::paint [0x158DF2C4+36]
STDERR: 	blink::PaintLayerPainter::paintFragmentWithPhase [0x157E926C+668]
STDERR: 	blink::PaintLayerPainter::paintBackgroundForFragments [0x157E87DC+140]
STDERR: 	blink::PaintLayerPainter::paintLayerContents [0x157EA08C+3084]
STDERR: 	blink::PaintLayerPainter::paintLayerContentsAndReflection [0x157EA3D8+216]
STDERR: 	blink::PaintLayerPainter::paintLayer [0x157E9464+468]
STDERR: 	blink::PaintLayerPainter::paintChildren [0x157E8A49+409]
STDERR: 	blink::PaintLayerPainter::paintLayerContents [0x157EA14A+3274]
STDERR: 	blink::PaintLayerPainter::paintLayerContentsAndReflection [0x157EA3D8+216]
STDERR: 	blink::PaintLayerPainter::paintLayer [0x157E9464+468]
STDERR: 	blink::PaintLayerPainter::paintChildren [0x157E8A49+409]
STDERR: 	blink::PaintLayerPainter::paintLayerContents [0x157EA14A+3274]
STDERR: 	blink::PaintLayerPainter::paintLayerContentsAndReflection [0x157EA3D8+216]
STDERR: 	blink::PaintLayerPainter::paintLayer [0x157E9464+468]
STDERR: 	blink::PaintLayerPainter::paintChildren [0x157E8A49+409]
STDERR: 	blink::PaintLayerPainter::paintLayerContents [0x157EA14A+3274]
STDERR: 	blink::CompositedLayerMapping::doPaintTask [0x159F1363+579]
STDERR: 	blink::CompositedLayerMapping::paintContents [0x159F259E+702]
STDERR: 	blink::GraphicsLayer::paintWithoutCommit [0x07A00EF3+499]
STDERR: 	blink::GraphicsLayer::paint [0x07A00A3C+44]
STDERR: 	blink::FrameView::synchronizedPaintRecursively [0x155D1B76+38]
STDERR: 	blink::FrameView::synchronizedPaintRecursively [0x155D1C26+214]
STDERR: 	blink::FrameView::synchronizedPaintRecursively [0x155D1C26+214]
STDERR: 	blink::FrameView::synchronizedPaintRecursively [0x155D1C26+214]
STDERR: 	blink::FrameView::synchronizedPaintRecursively [0x155D1C26+214]
STDERR: 	blink::FrameView::synchronizedPaint [0x155D1AB9+601]
STDERR: 	blink::FrameView::updateLifecyclePhasesInternal [0x155D2E57+1271]
STDERR: 	blink::FrameView::updateAllLifecyclePhases [0x155D24F6+38]
STDERR: 	blink::PageAnimator::updateAllLifecyclePhases [0x1576E5FD+45]
STDERR: 	blink::PageWidgetDelegate::updateAllLifecyclePhases [0x0CF480A8+24]
STDERR: 	blink::WebViewImpl::updateAllLifecyclePhases [0x0D037E44+260]
STDERR: 	test_runner::WebWidgetTestClient::AnimateNow [0x0EC0748E+142]
STDERR: 	??$Invoke@ABV?$WeakPtr@VWebWidgetTestClient@test_runner@@@base@@$$V@?$FunctorTraits@P8WebWidgetTestClient@test_runner@@AEXXZX@internal@base@@SAXP8WebWidgetTestClient@test_runner@@AEXXZABV?$WeakPtr@VWebWidgetTestClient@test_runner@@@2@@Z [0x0EC06D85+21]
STDERR: 	??$MakeItSo@ABQ8WebWidgetTestClient@test_runner@@AEXXZABV?$WeakPtr@VWebWidgetTestClient@test_runner@@@base@@$$V@?$InvokeHelper@$00X@internal@base@@SAXABQ8WebWidgetTestClient@test_runner@@AEXXZABV?$WeakPtr@VWebWidgetTestClient@test_runner@@@2@@Z [0x0EC06DF5+53]
STDERR: 	base::internal::Invoker<base::internal::BindState<void (__thiscall test_runner::WebWidgetTestClient::*)(void),base::WeakPtr<test_runner::WebWidgetTestClient> >,void __cdecl(void)>::RunImpl<void (__thiscall test_runner::WebWidgetTestClient::*const &)(void) [0x0EC06E44+52]

No more crashes according to http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=compositing%2Foverflow%2Fupdating-scrolling-container-and-content.html.

The image failures are because of  bug 627798  which has been fixed. Will rebaseline the test expectations.