[CSS Shapes] clamp RasterShape shapeMargin to reference box size

Source/core/rendering/shapes/RasterShape.cpp

 /*
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above
  *    copyright notice, this list of conditions and the following
  *    disclaimer.
@@ skipping 237 matching lines @@
 
     return result.release();
 }
 
 const RasterShapeIntervals& RasterShape::marginIntervals() const
 {
     ASSERT(shapeMargin() >= 0);
     if (!shapeMargin())
         return *m_intervals;
 
-    int marginBoundaryRadius = std::min(clampToInteger(ceil(shapeMargin())), std::max(m_imageSize.width(), m_imageSize.height()));
-    if (!m_marginIntervals) {
-        ASSERT(marginBoundaryRadius >= 0);
-        m_marginIntervals = m_intervals->computeShapeMarginIntervals(marginBoundaryRadius);
-    }
+    int shapeMarginInt = clampToPositiveInteger(ceil(shapeMargin()));
+    int maxShapeMarginInt = std::max(m_marginRectSize.width(), m_marginRectSize.height()) * sqrtf(2);
+    if (!m_marginIntervals)
+        m_marginIntervals = m_intervals->computeShapeMarginIntervals(std::min(shapeMarginInt, maxShapeMarginInt));
 
     return *m_marginIntervals;
 }
 
 const RasterShapeIntervals& RasterShape::paddingIntervals() const
 {
     ASSERT(shapePadding() >= 0);
     if (!shapePadding())
         return *m_intervals;
 
@@ skipping 32 matching lines @@
 bool RasterShape::firstIncludedIntervalLogicalTop(LayoutUnit minLogicalIntervalTop, const FloatSize& minLogicalIntervalSize, LayoutUnit& result) const
 {
     const RasterShapeIntervals& intervals = paddingIntervals();
     if (intervals.isEmpty())
         return false;
 
     return intervals.firstIncludedIntervalY(minLogicalIntervalTop.floor(), flooredIntSize(minLogicalIntervalSize), result);
 }
 
 } // namespace WebCore