ChangeLog

2012-07-10  Julien Chaffraix  <jchaffraix@webkit.org>

        REGRESSION (r116203): overflow sections don't have scrollbars

        https://bugs.webkit.org/show_bug.cgi?id=90052

        Reviewed by NOBODY (OOPS!).

        This issue stems from RenderLayers with overlay scrollbars not being considered

        self-painting.

        After r120395 (follow-up of r116203), we ignore subtree that have no self-painting layers for

        painting. Normal scrollbars are painted by their renderer so they were properly painted. However

        overlay scrollbars needs to be painted by the RenderLayer as a separate phase (see bug 57057) so

        they were not painted anymore. The fix is simple: make RenderLayer with overlay scrollbars

        self-painting as they should have been in the first place.

        Unfortunately no tests as I don't think we have a good way of testing overlay

        scrollbars. Tested manually though on the super simple test case from the bug.

        * rendering/RenderLayer.cpp:

        (WebCore::RenderLayer::shouldBeSelfPaintingLayer):

        Overlay scrollbars make the layer self-painting.

        (WebCore::RenderLayer::updateScrollbarsAfterLayout):

        Added a call to updateSelfPaintingLayer.

        (WebCore::RenderLayer::styleChanged):

        Moved the call to updateSelfPaintingLayer after recomputing the scrollbars to ensure proper behavior.

        Added a comment underlining the reason.

        (WebCore::RenderLayer::updateSelfPaintingLayer):

        Renamed as it is now called during layout too.

        * rendering/RenderLayer.h:

        (RenderLayer): Updated after updateSelfPaintingLayer rename.

2012-07-10  Ojan Vafai  <ojan@chromium.org>

        Add support for min-height:auto and min-width:auto

Source/WebCore/rendering/RenderLayer.cpp

@@void RenderLayer::updateScrollbarsAfterLayout()

        if (box->hasAutoVerticalScrollbar())

            setHasVerticalScrollbar(hasVerticalOverflow);

2537 updateSelfPaintingLayer();

2538

#if ENABLE(DASHBOARD_SUPPORT)

        // Force an update since we know the scrollbars have changed things.

        if (renderer()->document()->hasDashboardRegions())

@@bool RenderLayer::shouldBeNormalFlowOnly() const

bool RenderLayer::shouldBeSelfPaintingLayer() const

{

    return !isNormalFlowOnly()

4745 || hasOverlayScrollbars()

        || renderer()->hasReflection()

        || renderer()->hasMask()

        || renderer()->isTableRow()

@@bool RenderLayer::shouldBeSelfPaintingLayer() const

        || renderer()->isRenderIFrame();

}

4753 void RenderLayer::updateSelfPaintingLayer~~AfterStyleChange~~(const RenderStyle*)

4756void RenderLayer::updateSelfPaintingLayer()

{

    bool isSelfPaintingLayer = shouldBeSelfPaintingLayer();

    if (m_isSelfPaintingLayer == isSelfPaintingLayer)

@@void RenderLayer::styleChanged(StyleDifference, const RenderStyle* oldStyle)

        m_marquee = 0;

    }

4848 updateSelfPaintingLayerAfterStyleChange(oldStyle);

48494851 updateStackingContextsAfterStyleChange(oldStyle);

48504852 updateScrollbarsAfterStyleChange(oldStyle);

    // Overlay scrollbars can make this layer self-painting so we need

    // to recompute the bit once scrollbars have been updated.

    updateSelfPaintingLayer();

    if (!hasReflection() && m_reflection)

        removeReflection();

Source/WebCore/rendering/RenderLayer.h

@@private:

    bool shouldRepaintAfterLayout() const;

682 void updateSelfPaintingLayer~~AfterStyleChange(const RenderStyle* oldStyle~~);

682 void updateSelfPaintingLayer();

    void updateStackingContextsAfterStyleChange(const RenderStyle* oldStyle);

    void updateScrollbarsAfterStyleChange(const RenderStyle* oldStyle);