Don't cache subsequence whose layer is not fully contained by repaint rect

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 2400 matching lines @@
 void FrameView::updateWidgetPositionsIfNeeded()
 {
     if (!m_needsUpdateWidgetPositions)
         return;
 
     m_needsUpdateWidgetPositions = false;
 
     updateWidgetPositions();
 }
 
-void FrameView::updateAllLifecyclePhases()
+void FrameView::updateAllLifecyclePhases(const LayoutRect& interestRect)
 {
-    frame().localFrameRoot()->view()->updateLifecyclePhasesInternal(AllPhases);
+    frame().localFrameRoot()->view()->updateLifecyclePhasesInternal(AllPhases, interestRect);
 }
 
 // TODO(chrishtr): add a scrolling update lifecycle phase.
 void FrameView::updateLifecycleToCompositingCleanPlusScrolling()
 {
     frame().localFrameRoot()->view()->updateLifecyclePhasesInternal(OnlyUpToCompositingCleanPlusScrolling);
 }
 
-void FrameView::updateLifecyclePhasesInternal(LifeCycleUpdateOption phases)
+void FrameView::updateLifecyclePhasesInternal(LifeCycleUpdateOption phases, const LayoutRect& interestRect)
 {
     // This must be called from the root frame, since it recurses down, not up.
     // Otherwise the lifecycles of the frames might be out of sync.
     ASSERT(m_frame->isLocalRoot());
 
     // Updating layout can run script, which can tear down the FrameView.
     RefPtrWillBeRawPtr<FrameView> protector(this);
 
     updateStyleAndLayoutIfNeededRecursive();
 
     if (LayoutView* view = layoutView()) {
         TRACE_EVENT1("devtools.timeline", "UpdateLayerTree", "data", InspectorUpdateLayerTreeEvent::data(m_frame.get()));
 
         // This was required for slimming paint v1 but is only temporarily
         // needed for slimming paint v2.
         view->compositor()->updateIfNeededRecursive();
         scrollContentsIfNeededRecursive();
 
         ASSERT(lifecycle().state() >= DocumentLifecycle::CompositingClean);
 
         if (phases == AllPhases) {
             invalidateTreeIfNeededRecursive();
 
             if (view->compositor()->inCompositingMode())
                 scrollingCoordinator()->updateAfterCompositingChangeIfNeeded();
 
             updateCompositedSelectionIfNeeded();
 
             if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
-                paintForSlimmingPaintV2();
+                paintForSlimmingPaintV2(interestRect);
                 compositeForSlimmingPaintV2();
             }
 
             if (RuntimeEnabledFeatures::frameTimingSupportEnabled())
                 updateFrameTimingRequestsIfNeeded();
 
             ASSERT(!view->hasPendingSelection());
             ASSERT(lifecycle().state() == DocumentLifecycle::PaintInvalidationClean
                 || (RuntimeEnabledFeatures::slimmingPaintV2Enabled() && lifecycle().state() == DocumentLifecycle::CompositingForSlimmingPaintV2Clean));
         }
     }
 }
 
-void FrameView::paintForSlimmingPaintV2()
+void FrameView::paintForSlimmingPaintV2(const LayoutRect& interestRect)
 {
     ASSERT(RuntimeEnabledFeatures::slimmingPaintV2Enabled());
     ASSERT(frame() == page()->mainFrame() || (!frame().tree().parent()->isLocalFrame()));
 
     LayoutView* view = layoutView();
     ASSERT(view);
     GraphicsLayer* rootGraphicsLayer = view->layer()->graphicsLayerBacking();
 
     // Detached frames can have no root graphics layer.
     if (!rootGraphicsLayer)
         return;
 
     lifecycle().advanceTo(DocumentLifecycle::InPaintForSlimmingPaintV2);
 
-    // TODO(pdr): Update callers to pass in the interest rect.
-    IntRect interestRect = LayoutRect::infiniteIntRect();
     GraphicsContext context(rootGraphicsLayer->displayItemList());
-    rootGraphicsLayer->paint(context, interestRect);
+    rootGraphicsLayer->paint(context, roundedIntRect(interestRect));
 
     lifecycle().advanceTo(DocumentLifecycle::PaintForSlimmingPaintV2Clean);
 }
 
 void FrameView::compositeForSlimmingPaintV2()
 {
     ASSERT(RuntimeEnabledFeatures::slimmingPaintV2Enabled());
     ASSERT(frame() == page()->mainFrame() || (!frame().tree().parent()->isLocalFrame()));
 
     GraphicsLayer* rootGraphicsLayer = layoutView()->layer()->graphicsLayerBacking();
@@ skipping 1436 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