(WIP) Invalidation during painting (for synchronized painting)

third_party/WebKit/Source/core/paint/LayoutObjectDrawingRecorder.h

 // 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.
 
 #ifndef LayoutObjectDrawingRecorder_h
 #define LayoutObjectDrawingRecorder_h
 
 #include "core/layout/LayoutObject.h"
 #include "core/paint/PaintPhase.h"
 #include "platform/geometry/LayoutPoint.h"
 #include "platform/geometry/LayoutRect.h"
 #include "platform/graphics/paint/DisplayItemCacheSkipper.h"
 #include "platform/graphics/paint/DrawingRecorder.h"
 #include "wtf/Allocator.h"
 #include "wtf/Optional.h"
 
 namespace blink {
 
 class GraphicsContext;
 
 // Convenience wrapper of DrawingRecorder for LayoutObject painters.
 class LayoutObjectDrawingRecorder final {
     DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
 public:
-    static bool useCachedDrawingIfPossible(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType, const LayoutPoint& paintOffset)
+    static bool useCachedDrawingIfPossible(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType)
     {
-        if (RuntimeEnabledFeatures::slimmingPaintOffsetCachingEnabled() && layoutObject.paintOffsetChanged(paintOffset))
-            return false;
         if (layoutObject.fullPaintInvalidationReason() == PaintInvalidationDelayedFull)
             return false;
         return DrawingRecorder::useCachedDrawingIfPossible(context, layoutObject, displayItemType);
     }
 
-    static bool useCachedDrawingIfPossible(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const LayoutPoint& paintOffset)
+    static bool useCachedDrawingIfPossible(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase)
     {
-        return useCachedDrawingIfPossible(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), paintOffset);
+        return useCachedDrawingIfPossible(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase));
     }
 
-    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType, const FloatRect& clip, const LayoutPoint& paintOffset)
+    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType, const FloatRect& clip)
     {
-        updatePaintOffsetIfNeeded(context.paintController(), layoutObject, paintOffset);
         // We may paint a delayed-invalidation object before it's actually invalidated.
         if (layoutObject.fullPaintInvalidationReason() == PaintInvalidationDelayedFull)
             m_cacheSkipper.emplace(context);
         m_drawingRecorder.emplace(context, layoutObject, displayItemType, clip);
     }
 
-    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType, const LayoutRect& clip, const LayoutPoint& paintOffset)
-        : LayoutObjectDrawingRecorder(context, layoutObject, displayItemType, FloatRect(clip), paintOffset) { }
+    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, DisplayItem::Type displayItemType, const LayoutRect& clip)
+        : LayoutObjectDrawingRecorder(context, layoutObject, displayItemType, FloatRect(clip)) { }
 
-    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const FloatRect& clip, const LayoutPoint& paintOffset)
-        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), clip, paintOffset) { }
+    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const FloatRect& clip)
+        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), clip) { }
 
-    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const LayoutRect& clip, const LayoutPoint& paintOffset)
-        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), FloatRect(clip), paintOffset) { }
+    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const LayoutRect& clip)
+        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), FloatRect(clip)) { }
 
-    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const IntRect& clip, const LayoutPoint& paintOffset)
-        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), FloatRect(clip), paintOffset) { }
+    LayoutObjectDrawingRecorder(GraphicsContext& context, const LayoutObject& layoutObject, PaintPhase phase, const IntRect& clip)
+        : LayoutObjectDrawingRecorder(context, layoutObject, DisplayItem::paintPhaseToDrawingType(phase), FloatRect(clip)) { }
 
     void setKnownToBeOpaque() { ASSERT(RuntimeEnabledFeatures::slimmingPaintV2Enabled()); m_drawingRecorder->setKnownToBeOpaque(); }
 
 #if ENABLE(ASSERT)
     void setUnderInvalidationCheckingMode(DrawingDisplayItem::UnderInvalidationCheckingMode mode) { m_drawingRecorder->setUnderInvalidationCheckingMode(mode); }
 #endif
 
 private:
-    static void updatePaintOffsetIfNeeded(PaintController& paintController, const LayoutObject& layoutObject, const LayoutPoint& paintOffset)
-    {
-        if (!RuntimeEnabledFeatures::slimmingPaintOffsetCachingEnabled() || paintController.skippingCache())
-            return;
-
-        if (layoutObject.paintOffsetChanged(paintOffset))
-            paintController.invalidatePaintOffset(layoutObject);
-        else
-            ASSERT(!paintController.paintOffsetWasInvalidated(layoutObject) || !paintController.clientCacheIsValid(layoutObject));
-
-        layoutObject.mutableForPainting().setPreviousPaintOffset(paintOffset);
-    }
-
     Optional<DisplayItemCacheSkipper> m_cacheSkipper;
     Optional<DrawingRecorder> m_drawingRecorder;
 };
 
 } // namespace blink
 
 #endif // LayoutObjectDrawingRecorder_h