[CSS Shapes] shape-margin in percentage units always computes to 0px

Source/core/rendering/shapes/ShapeOutsideInfo.cpp

 /*
  * Copyright (C) 2012 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 16 matching lines @@
  * SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/rendering/shapes/ShapeOutsideInfo.h"
 
 #include "core/rendering/FloatingObjects.h"
 #include "core/rendering/RenderBlockFlow.h"
 #include "core/rendering/RenderBox.h"
 #include "core/rendering/RenderImage.h"
+#include "platform/LengthFunctions.h"
 
 namespace WebCore {
 
 CSSBoxType referenceBox(const ShapeValue& shapeValue)
 {
     if (shapeValue.cssBox() == BoxMissing)
         return MarginBox;
     return shapeValue.cssBox();
 }
 
@@ skipping 69 matching lines @@
 const Shape& ShapeOutsideInfo::computedShape() const
 {
     if (Shape* shape = m_shape.get())
         return *shape;
 
     const RenderStyle& style = *m_renderer.style();
     ASSERT(m_renderer.containingBlock());
     const RenderStyle& containingBlockStyle = *m_renderer.containingBlock()->style();
 
     WritingMode writingMode = containingBlockStyle.writingMode();
-    Length margin = style.shapeMargin();
+    LayoutUnit maximumValue = m_renderer.containingBlock() ? m_renderer.containingBlock()->contentWidth() : LayoutUnit();
+    float margin = floatValueForLength(m_renderer.style()->shapeMargin(), maximumValue.toFloat());
+
     float shapeImageThreshold = style.shapeImageThreshold();
     ASSERT(style.shapeOutside());
     const ShapeValue& shapeValue = *style.shapeOutside();
 
     switch (shapeValue.type()) {
     case ShapeValue::Shape:
         ASSERT(shapeValue.shape());
         m_shape = Shape::createShape(shapeValue.shape(), m_referenceBoxLogicalSize, writingMode, margin);
         break;
     case ShapeValue::Image: {
@@ skipping 161 matching lines @@
         // Lines that do not overlap the shape should act as if the float
         // wasn't there for layout purposes. So we set the deltas to remove the
         // entire width of the float.
         m_leftMarginBoxDelta = floatMarginBoxWidth;
         m_rightMarginBoxDelta = -floatMarginBoxWidth;
         m_lineOverlapsShape = false;
     }
 }
 
 }