Oilpan: improve ScrollableArea handling.

Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 147 matching lines @@
     RefPtrWillBeRawPtr<FrameView> view = adoptRefWillBeNoop(new FrameView(frame));
     view->Widget::setFrameRect(IntRect(view->location(), initialSize));
     view->setLayoutSizeInternal(initialSize);
 
     view->show();
     return view.release();
 }
 
 FrameView::~FrameView()
 {
-#if ENABLE(ASSERT)
     ASSERT(m_hasBeenDisposed);
-#endif
 #if !ENABLE(OILPAN)
     // Verify that the LocalFrame has a different FrameView or
     // that it is being detached and destructed.
     ASSERT(frame().view() != this || !layoutView());
 #endif
 }
 
 DEFINE_TRACE(FrameView)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_frame);
     visitor->trace(m_nodeToDraw);
     visitor->trace(m_maintainScrollPositionAnchor);
+    visitor->trace(m_scrollableAreas);
+    visitor->trace(m_animatingScrollableAreas);
     visitor->trace(m_autoSizeInfo);
     visitor->trace(m_horizontalScrollbar);
     visitor->trace(m_verticalScrollbar);
     visitor->trace(m_children);
+    visitor->trace(m_viewportScrollableArea);
 #endif
     Widget::trace(visitor);
+    ScrollableArea::trace(visitor);
 }
 
 void FrameView::reset()
 {
     m_hasPendingLayout = false;
     m_doFullPaintInvalidation = false;
     m_layoutSchedulingEnabled = true;
     m_inPerformLayout = false;
     m_inSynchronousPostLayout = false;
     m_layoutCount = 0;
@@ skipping 1667 matching lines @@
     RefPtrWillBeRawPtr<Node> anchorNode = m_maintainScrollPositionAnchor;
     if (!anchorNode)
         return;
 
     if (!anchorNode->layoutObject())
         return;
 
     LayoutRect rect;
     if (anchorNode != m_frame->document()) {
         rect = anchorNode->boundingBox();
-    } else if (m_frame->settings()->rootLayerScrolls()) {
+    } else if (m_frame->settings() && m_frame->settings()->rootLayerScrolls()) {
         if (Element* documentElement = m_frame->document()->documentElement())
             rect = documentElement->boundingBox();
     }
 
     RefPtrWillBeRawPtr<Frame> boundaryFrame = m_frame->findUnsafeParentScrollPropagationBoundary();
 
     // FIXME: Handle RemoteFrames
     if (boundaryFrame && boundaryFrame->isLocalFrame())
         toLocalFrame(boundaryFrame.get())->view()->setSafeToPropagateScrollToParent(false);
 
@@ skipping 971 matching lines @@
 
     ResizerAreaSet::iterator it = m_resizerAreas->find(&resizerBox);
     if (it != m_resizerAreas->end())
         m_resizerAreas->remove(it);
 }
 
 void FrameView::addScrollableArea(ScrollableArea* scrollableArea)
 {
     ASSERT(scrollableArea);
     if (!m_scrollableAreas)
-        m_scrollableAreas = adoptPtr(new ScrollableAreaSet);
+        m_scrollableAreas = adoptPtrWillBeNoop(new ScrollableAreaSet);
     m_scrollableAreas->add(scrollableArea);
 
     if (ScrollingCoordinator* scrollingCoordinator = this->scrollingCoordinator())
         scrollingCoordinator->scrollableAreasDidChange();
 }
 
 void FrameView::removeScrollableArea(ScrollableArea* scrollableArea)
 {
     if (!m_scrollableAreas)
         return;
     m_scrollableAreas->remove(scrollableArea);
 
     if (ScrollingCoordinator* scrollingCoordinator = this->scrollingCoordinator())
         scrollingCoordinator->scrollableAreasDidChange();
 }
 
 void FrameView::addAnimatingScrollableArea(ScrollableArea* scrollableArea)
 {
     ASSERT(scrollableArea);
     if (!m_animatingScrollableAreas)
-        m_animatingScrollableAreas = adoptPtr(new ScrollableAreaSet);
+        m_animatingScrollableAreas = adoptPtrWillBeNoop(new ScrollableAreaSet);
     m_animatingScrollableAreas->add(scrollableArea);
 }
 
 void FrameView::removeAnimatingScrollableArea(ScrollableArea* scrollableArea)
 {
     if (!m_animatingScrollableAreas)
         return;
     m_animatingScrollableAreas->remove(scrollableArea);
 }
 
@@ skipping 155 matching lines @@
         m_horizontalScrollbar->styleChanged();
     } else {
         willRemoveScrollbar(m_horizontalScrollbar.get(), HorizontalScrollbar);
         if (AXObjectCache* cache = axObjectCache())
             cache->remove(m_horizontalScrollbar.get());
         // If the scrollbar has been marked as overlapping the window resizer,
         // then its removal should reduce the count.
         if (m_horizontalScrollbar->overlapsResizer())
             adjustScrollbarsAvoidingResizerCount(-1);
         removeChild(m_horizontalScrollbar.get());
+        m_horizontalScrollbar->disconnectFromScrollableArea();

[haraken, 2015/06/30 10:30:35]

Shall we add #if !ENABLE(OILPAN)?

[sof, 2015/06/30 11:34:09]

No, I don't think it is worth adding the CPPery at the call sites at this stage.
We can remove the method once transitioned, so let's add a TODO there instead.

         m_horizontalScrollbar = nullptr;
         if (AXObjectCache* cache = axObjectCache())
             cache->handleScrollbarUpdate(this);
     }
 
     if (RuntimeEnabledFeatures::slimmingPaintEnabled())
         invalidateScrollCorner(scrollCornerRect());
 }
 
 void FrameView::setHasVerticalScrollbar(bool hasBar)
 {
     if (hasBar == !!m_verticalScrollbar)
         return;
 
     if (hasBar) {
         m_verticalScrollbar = createScrollbar(VerticalScrollbar);
         addChild(m_verticalScrollbar.get());
         didAddScrollbar(m_verticalScrollbar.get(), VerticalScrollbar);
         m_verticalScrollbar->styleChanged();
     } else {
         willRemoveScrollbar(m_verticalScrollbar.get(), VerticalScrollbar);
         if (AXObjectCache* cache = axObjectCache())
             cache->remove(m_verticalScrollbar.get());
         // If the scrollbar has been marked as overlapping the window resizer,
         // then its removal should reduce the count.
         if (m_verticalScrollbar->overlapsResizer())
             adjustScrollbarsAvoidingResizerCount(-1);
         removeChild(m_verticalScrollbar.get());
+        m_verticalScrollbar->disconnectFromScrollableArea();

[haraken, 2015/06/30 10:30:35]

#if !ENABLE(OILPAN)

         m_verticalScrollbar = nullptr;
         if (AXObjectCache* cache = axObjectCache())
             cache->handleScrollbarUpdate(this);
     }
 
     if (RuntimeEnabledFeatures::slimmingPaintEnabled())
         invalidateScrollCorner(scrollCornerRect());
 }
 
 void FrameView::setScrollbarModes(ScrollbarMode horizontalMode, ScrollbarMode verticalMode,
@@ skipping 868 matching lines @@
 
     if (!graphicsLayer)
         return;
 
     DeprecatedPaintLayer::mapRectToPaintInvalidationBacking(localFrame->contentLayoutObject(), paintInvalidationContainer, viewRect);
 
     graphicsLayerTimingRequests.add(graphicsLayer, Vector<std::pair<int64_t, WebRect>>()).storedValue->value.append(std::make_pair(m_frame->frameID(), enclosingIntRect(viewRect)));
 }
 
 } // namespace blink