[CSS Shapes] clamp RasterShape shapeMargin to reference box size

Source/core/rendering/shapes/RasterShape.cpp

Index: Source/core/rendering/shapes/RasterShape.cpp
diff --git a/Source/core/rendering/shapes/RasterShape.cpp b/Source/core/rendering/shapes/RasterShape.cpp
index 996a8b8625ae26012a68583461ec5425aa72ee09..da08eedb651c0113b8cd19d7faf1156f465c6392 100644
--- a/Source/core/rendering/shapes/RasterShape.cpp
+++ b/Source/core/rendering/shapes/RasterShape.cpp
@@ -255,11 +255,10 @@ const RasterShapeIntervals& RasterShape::marginIntervals() const
     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;
 }