[svg2] Make 'x' and 'y' presentation attributes

Source/core/svg/SVGLengthContext.cpp

Index: Source/core/svg/SVGLengthContext.cpp
diff --git a/Source/core/svg/SVGLengthContext.cpp b/Source/core/svg/SVGLengthContext.cpp
index a37ddb11a53d53012ad56419fc5730e5ac6d01b0..e11f90e4d300dc929f9c3f74dea55e76964669ae 100644
--- a/Source/core/svg/SVGLengthContext.cpp
+++ b/Source/core/svg/SVGLengthContext.cpp
@@ -27,6 +27,7 @@
 #include "core/layout/LayoutObject.h"
 #include "core/layout/style/LayoutStyle.h"
 #include "core/svg/SVGSVGElement.h"
+#include "platform/LengthFunctions.h"
 #include "platform/fonts/FontMetrics.h"
 
 namespace blink {
@@ -95,6 +96,20 @@ float SVGLengthContext::resolveLength(const SVGElement* context, SVGUnitTypes::S
     return x.valueAsPercentage();
 }
 
+float SVGLengthContext::valueForLength(const Length& length, SVGLengthMode mode)
+{
+    if (length.isAuto())
+        return 0;
+
+    FloatSize viewportSize;
+    determineViewport(viewportSize);
+
+    if (length.isPercent())
+        return length.value() * dimensionForLengthMode(mode, viewportSize) / 100;
+
+    return floatValueForLength(length, dimensionForLengthMode(mode, viewportSize));
+}
+
 float SVGLengthContext::convertValueToUserUnits(float value, SVGLengthMode mode, SVGLengthType fromUnit) const
 {
     switch (fromUnit) {