Add static root property tree nodes [spv2]

third_party/WebKit/Source/core/paint/FramePainter.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/FramePainter.h"
 
 #include "core/editing/markers/DocumentMarkerController.h"
 #include "core/fetch/MemoryCache.h"
 #include "core/frame/FrameView.h"
 #include "core/inspector/InspectorInstrumentation.h"
@@ skipping 28 matching lines @@
     bool shouldPaintScrollbars = !frameView().scrollbarsSuppressed() && (frameView().horizontalScrollbar() || frameView().verticalScrollbar());
     if (!shouldPaintContents && !shouldPaintScrollbars)
         return;
 
     if (shouldPaintContents) {
         // TODO(pdr): Creating frame paint properties here will not be needed once
         // settings()->rootLayerScrolls() is enabled.
         // TODO(pdr): Make this conditional on the rootLayerScrolls setting.
         Optional<ScopedPaintChunkProperties> scopedPaintChunkProperties;
         if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
-            TransformPaintPropertyNode* transform = m_frameView->scrollTranslation() ? m_frameView->scrollTranslation() : m_frameView->preTranslation();
-            ClipPaintPropertyNode* clip = m_frameView->contentClip();
-            ScrollPaintPropertyNode* scroll = m_frameView->scroll();
-            PaintChunkProperties properties(context.getPaintController().currentPaintChunkProperties());
-            if (frameView().frame().isLocalRoot()) {
-                properties.transform = frameView().rootTransform();
-                properties.clip = frameView().rootClip();
-                properties.effect = frameView().rootEffect();
-            }
-            if (transform || clip || scroll) {
-                if (transform)
-                    properties.transform = transform;
-                if (scroll)
-                    properties.scroll = scroll;
-                if (clip)
-                    properties.clip = clip;
+            if (const PropertyTreeState* contentsState = m_frameView->totalPropertyTreeStateForContents()) {

[pdr., 2016/09/22 19:48:20]

This change caught a real bug where FramePainter was using a null scrollNode
here. I've fixed the test
(PaintControllerPaintTestForSlimmingPaintV2.ChunkIdClientCacheFlag) and added a
check specifically that we don't have a null node.

+                PaintChunkProperties properties(context.getPaintController().currentPaintChunkProperties());
+                properties.transform = contentsState->transform;
+                properties.clip = contentsState->clip;
+                properties.effect = contentsState->effect;
+                properties.scroll = contentsState->scroll;
                 scopedPaintChunkProperties.emplace(context.getPaintController(), *frameView().layoutView(), properties);
             }
         }
 
         TransformRecorder transformRecorder(context, *frameView().layoutView(),
             AffineTransform::translation(frameView().x() - frameView().scrollX(), frameView().y() - frameView().scrollY()));
 
         ClipRecorder recorder(context, *frameView().layoutView(), DisplayItem::kClipFrameToVisibleContentRect, frameView().visibleContentRect());
 
         documentDirtyRect.moveBy(-frameView().location() + frameView().scrollPosition());
@@ skipping 130 matching lines @@
     bar.paint(context, CullRect(rect));
 }
 
 const FrameView& FramePainter::frameView()
 {
     ASSERT(m_frameView);
     return *m_frameView;
 }
 
 } // namespace blink