ChangeLog

2020-02-20  Zalan Bujtas  <zalan@apple.com>

        [First paint] FrameView::loadProgressingStatusChanged should check m_firstVisuallyNonEmptyLayoutMilestoneIsPending

        https://bugs.webkit.org/show_bug.cgi?id=208008

        <rdar://problem/59630957>

        Reviewed by NOBODY (OOPS!).

        If we haven't had a chance to issue a visually-non-empty milestone, we definitely need to check the content again when the load

        is finally completed.

        * page/FrameView.cpp:

        (WebCore::FrameView::loadProgressingStatusChanged):

2020-02-20  Zalan Bujtas  <zalan@apple.com>

        [LFC] Sometimes subframes don't even have document elements.

Source/WebCore/page/FrameView.cpp

@@void FrameView::disableLayerFlushThrottlingTemporarilyForInteraction()

void FrameView::loadProgressingStatusChanged()

{

2853 if (!~~m_contentQualifiesAs~~VisuallyNonEmpty && frame().loader().isComplete())

2853 if (m_firstVisuallyNonEmptyLayoutMilestoneIsPending && frame().loader().isComplete())

        fireLayoutRelatedMilestonesIfNeeded();

    updateLayerFlushThrottling();

    adjustTiledBackingCoverage();