[SVG2] Make transform, gradientTransform and patternTransform presentation attributes.

Source/core/svg/SVGElement.cpp

Index: Source/core/svg/SVGElement.cpp
diff --git a/Source/core/svg/SVGElement.cpp b/Source/core/svg/SVGElement.cpp
index b051e1370a0efd813e68648ca7c7e50a9d753230..c6537d2c5e65533a00c7a2f090d9762c91d63888 100644
--- a/Source/core/svg/SVGElement.cpp
+++ b/Source/core/svg/SVGElement.cpp
@@ -1191,4 +1191,36 @@ const AtomicString& SVGElement::eventParameterName()
     return evtString;
 }
 
+bool SVGElement::getStyleTransform(AffineTransform& matrix) const
+{
+    RenderStyle* style = renderer() ? renderer()->style() : 0;
+    if (style && style->hasTransform()) {
+        TransformationMatrix transform;
+        float zoom = style->effectiveZoom();
+
+        // CSS transforms operate with pre-scaled lengths. To make this work with SVG
+        // (which applies the zoom factor globally, at the root level) we
+        //
+        //   * pre-scale the bounding box (to bring it into the same space as the other CSS values)
+        //   * invert the zoom factor (to effectively compute the CSS transform under a 1.0 zoom)
+        //
+        // Note: objectBoundingBox is an emptyRect for elements like pattern or clipPath.
+        // See the "Object bounding box units" section of http://dev.w3.org/csswg/css3-transforms/
+        if (zoom != 1) {
+            FloatRect scaledBBox = renderer()->objectBoundingBox();
+            scaledBBox.scale(zoom);
+            transform.scale(1 / zoom);
+            style->applyTransform(transform, scaledBBox);
+            transform.scale(zoom);
+        } else {
+            style->applyTransform(transform, renderer()->objectBoundingBox());
+        }
+
+        // Flatten any 3D transform.
+        matrix = transform.toAffineTransform();
+        return true;
+    }
+    return false;
+}
+
 }