Chrome Version: 66.0.3341.0 (Developer Build) (64-bit)
OS: Linux, have not tried others

What steps will reproduce the problem?
1. Run with DCHECKs on
2. Open a PDF, e.g. https://www.irs.gov/pub/irs-prior/f1040ez--2017.pdf
3. Open Print Preview
4. Open dev tools for print preview page, and ensure the selected element is not inside the preview area iframe.
5. Execute the following lines in the console:
let di = document.createElement('dialog');
document.body.appendChild(di);
di.showModal()

What is the expected result?
Empty modal dialog should appear on print preview page.

What happens instead?
DCHECK crash. Trace pasted below.

Note - this does not occur on print previews of webpages (e.g. www.google.com). Also does not occur if an element of the preview area iframe is selected in dev tools, for example, the plugin embed element.

Trace: 
[1:1:0208/163026.850222:FATAL:FindPropertiesNeedingUpdate.h(91)] Check failed: !!original_scroll_node_ == !!frame_view_->ScrollNode(). Property was created or deleted without the LocalFrameView needing a paint property update.
Original:
 0x371596d84fd0 {"parent":"0x371596d84310","containerRect":"0,0 1319x710","contentsRect":"0,0 1319x3560","userScrollable":"both","compositorElementId":"(610)"}
Updated:
null
#0 0x7fcfd2458a7d base::debug::StackTrace::StackTrace()
#1 0x7fcfd2456f6c base::debug::StackTrace::StackTrace()
#2 0x7fcfd24df99a logging::LogMessage::~LogMessage()
#3 0x7fcfc04d2646 blink::FindFrameViewPropertiesNeedingUpdateScope::~FindFrameViewPropertiesNeedingUpdateScope()
#4 0x7fcfc04c85c0 blink::FrameViewPaintPropertyTreeBuilder::Update()
#5 0x7fcfc04f5f3f blink::PrePaintTreeWalk::Walk()
#6 0x7fcfc04f64f5 blink::PrePaintTreeWalk::Walk()
#7 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#8 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#9 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#10 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#11 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#12 0x7fcfc04f62e2 blink::PrePaintTreeWalk::Walk()
#13 0x7fcfc04f60d2 blink::PrePaintTreeWalk::Walk()
#14 0x7fcfc04f5c01 blink::PrePaintTreeWalk::Walk()
#15 0x7fcfbfb3bcf7 blink::LocalFrameView::PrePaint()
#16 0x7fcfbfb3a288 blink::LocalFrameView::UpdateLifecyclePhasesInternal()
#17 0x7fcfbfb39922 blink::LocalFrameView::UpdateAllLifecyclePhases()
#18 0x7fcfc03e5a2b blink::PageAnimator::UpdateAllLifecyclePhases()
#19 0x7fcfc03eae2c blink::PageWidgetDelegate::UpdateLifecycle()
#20 0x7fcfbfa5d318 blink::WebViewImpl::UpdateLifecycle()
#21 0x7fcfbfbce4b7 blink::WebViewFrameWidget::UpdateLifecycle()
#22 0x7fcfcdca95fb content::RenderWidget::UpdateVisualState()
#23 0x7fcfcda97a03 content::RenderWidgetCompositor::UpdateLayerTreeHost()
#24 0x7fcfc9e2e793 cc::LayerTreeHost::RequestMainFrameUpdate()
#25 0x7fcfc9f1efa0 cc::ProxyMain::BeginMainFrame()