Implement a paint offset cache for slimming paint v2

Source/core/paint/BlockPainter.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 "config.h"
 #include "core/paint/BlockPainter.h"
 
 #include "core/editing/DragCaretController.h"
 #include "core/editing/FrameSelection.h"
 #include "core/frame/Settings.h"
@@ skipping 185 matching lines @@
 
         if (paintPhase == PaintPhaseFloat || paintPhase == PaintPhaseSelection || paintPhase == PaintPhaseTextClip)
             m_layoutBlock.paintFloats(contentsPaintInfo, paintOffset, paintPhase == PaintPhaseSelection || paintPhase == PaintPhaseTextClip);
     }
 
     if ((paintPhase == PaintPhaseOutline || paintPhase == PaintPhaseSelfOutline) && m_layoutBlock.style()->hasOutline() && m_layoutBlock.style()->visibility() == VISIBLE)
         ObjectPainter(m_layoutBlock).paintOutline(paintInfo, paintOffset);
 
     // If the caret's node's layout object's containing block is this block, and the paint action is PaintPhaseForeground,
     // then paint the caret.
-    if (paintPhase == PaintPhaseForeground && hasCaret() && !LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutBlock, DisplayItem::Caret)) {
+    if (paintPhase == PaintPhaseForeground && hasCaret() && !LayoutObjectDrawingRecorder::useCachedDrawingIfPossible(*paintInfo.context, m_layoutBlock, DisplayItem::Caret, paintOffset)) {
         LayoutRect bounds = m_layoutBlock.visualOverflowRect();
         bounds.moveBy(paintOffset);
-        LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutBlock, DisplayItem::Caret, bounds);
+        LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutBlock, DisplayItem::Caret, bounds, paintOffset);
         paintCarets(paintInfo, paintOffset);
     }
 }
 
 static inline bool caretBrowsingEnabled(const LocalFrame* frame)
 {
     Settings* settings = frame->settings();
     return settings && settings->caretBrowsingEnabled();
 }
 
@@ skipping 57 matching lines @@
 
         // We don't paint our own background, but we do let the kids paint their backgrounds.
         PaintInfo paintInfoForChild(paintInfo);
         paintInfoForChild.phase = newPhase;
         paintInfoForChild.updatePaintingRootForChildren(&m_layoutBlock);
         m_layoutBlock.paintChildren(paintInfoForChild, paintOffset);
     }
 }
 
 } // namespace blink