SP: add a scope recorder for painting inline continuation outlines.

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/FrameSelection.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutFlexibleBox.h"
@@ skipping 305 matching lines @@
         for (LayoutBoxModelObject* box = inlineLayoutObject; box != cb; box = box->parent()->enclosingBoxModelObject()) {
             if (box->hasSelfPaintingLayer()) {
                 inlineEnclosedInSelfPaintingLayer = true;
                 break;
             }
         }
 
         // Do not add continuations for outline painting by our containing block if we are a relative positioned
         // anonymous block (i.e. have our own layer), paint them straightaway instead. This is because a block depends on layoutObjects in its continuation table being
         // in the same layer.
-        if (!inlineEnclosedInSelfPaintingLayer && !m_layoutBlock.hasLayer())
+        if (!inlineEnclosedInSelfPaintingLayer && !m_layoutBlock.hasLayer()) {
             cb->addContinuationWithOutline(inlineLayoutObject);
-        else if (!inlineLayoutObject->firstLineBox() || (!inlineEnclosedInSelfPaintingLayer && m_layoutBlock.hasLayer()))
+        } else if (!inlineLayoutObject->firstLineBox() || (!inlineEnclosedInSelfPaintingLayer && m_layoutBlock.hasLayer())) {
+            // The outline might be painted multiple times if multiple blocks have the same inline element continuation, and the inline has a self-painting layer.
+            ScopeRecorder scopeRecorder(*info.context, *inlineLayoutObject);
             InlinePainter(*inlineLayoutObject).paintOutline(info, paintOffset - m_layoutBlock.locationOffset() + inlineLayoutObject->containingBlock()->location());
+        }
     }
 
     ContinuationOutlineTableMap* table = continuationOutlineTable();
     if (table->isEmpty())
         return;
 
     OwnPtr<ListHashSet<LayoutInline*>> continuations = table->take(&m_layoutBlock);
     if (!continuations)
         return;
 
     LayoutPoint accumulatedPaintOffset = paintOffset;
     // Paint each continuation outline.
     ListHashSet<LayoutInline*>::iterator end = continuations->end();
     for (ListHashSet<LayoutInline*>::iterator it = continuations->begin(); it != end; ++it) {
         // Need to add in the coordinates of the intervening blocks.
         LayoutInline* flow = *it;
         LayoutBlock* block = flow->containingBlock();
         for ( ; block && block != &m_layoutBlock; block = block->containingBlock())
             accumulatedPaintOffset.moveBy(block->location());
         ASSERT(block);
         InlinePainter(*flow).paintOutline(info, accumulatedPaintOffset);
     }
 }
 
 
 } // namespace blink