[CSS Masking][CSS Shapes] Large corner radii use with inset() clip-path are not properly constrained

Source/core/rendering/style/BasicShapes.cpp

Index: Source/core/rendering/style/BasicShapes.cpp
diff --git a/Source/core/rendering/style/BasicShapes.cpp b/Source/core/rendering/style/BasicShapes.cpp
index 74c13eeb3f878146efb57a048123a9f828902b0b..c83c9579a5398a35ea124ebffba649ddefb7bb62 100644
--- a/Source/core/rendering/style/BasicShapes.cpp
+++ b/Source/core/rendering/style/BasicShapes.cpp
@@ -31,6 +31,7 @@
 #include "core/rendering/style/BasicShapes.h"
 
 #include "core/css/BasicShapeFunctions.h"
+#include "core/rendering/style/RenderStyle.h"
 #include "platform/CalculationValue.h"
 #include "platform/LengthFunctions.h"
 #include "platform/geometry/FloatRect.h"
@@ -227,18 +228,15 @@ void BasicShapeInset::path(Path& path, const FloatRect& boundingBox)
     ASSERT(path.isEmpty());
     float left = floatValueForLength(m_left, boundingBox.width());
     float top = floatValueForLength(m_top, boundingBox.height());
-    path.addRoundedRect(
-        FloatRect(
-            left + boundingBox.x(),
-            top + boundingBox.y(),
-            std::max<float>(boundingBox.width() - left - floatValueForLength(m_right, boundingBox.width()), 0),
-            std::max<float>(boundingBox.height() - top - floatValueForLength(m_bottom, boundingBox.height()), 0)
-        ),
-        floatSizeForLengthSize(m_topLeftRadius, boundingBox),
+    auto rect = FloatRect(left + boundingBox.x(), top + boundingBox.y(),

[leviw_travelin_and_unemployed, 2015/01/17 00:18:22]

Nit: I don't think auto makes things clearer here.

+        std::max<float>(boundingBox.width() - left - floatValueForLength(m_right, boundingBox.width()), 0),
+        std::max<float>(boundingBox.height() - top - floatValueForLength(m_bottom, boundingBox.height()), 0));
+    auto radii = FloatRoundedRect::Radii(floatSizeForLengthSize(m_topLeftRadius, boundingBox),
         floatSizeForLengthSize(m_topRightRadius, boundingBox),
         floatSizeForLengthSize(m_bottomLeftRadius, boundingBox),
-        floatSizeForLengthSize(m_bottomRightRadius, boundingBox)
-    );
+        floatSizeForLengthSize(m_bottomRightRadius, boundingBox));
+    radii.scale(calcBorderRadiiConstraintScaleFor(rect, radii));
+    path.addRoundedRect(FloatRoundedRect(rect, radii));
 }
 
 static inline LengthSize blendLengthSize(const LengthSize& to, const LengthSize& from, double progress)