Make 'transform' a presentation attribute on SVG elements

third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp

Index: third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp
diff --git a/third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp b/third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp
index 3a5da4ecef86c5f62415dea669813485efade5bd..be1cc458407d9aa9d6ebe630655a178687df3c7c 100644
--- a/third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp
+++ b/third_party/WebKit/Source/core/svg/SVGGraphicsElement.cpp
@@ -22,7 +22,8 @@
 #include "core/svg/SVGGraphicsElement.h"
 
 #include "core/SVGNames.h"
-#include "core/layout/svg/LayoutSVGPath.h"
+#include "core/dom/StyleChangeReason.h"
+#include "core/layout/LayoutObject.h"
 #include "core/svg/SVGElementRareData.h"
 #include "core/svg/SVGMatrixTearOff.h"
 #include "core/svg/SVGRectTearOff.h"
@@ -35,8 +36,9 @@ SVGGraphicsElement::SVGGraphicsElement(const QualifiedName& tagName,
                                        ConstructionType constructionType)
     : SVGElement(tagName, document, constructionType),
       SVGTests(this),
-      m_transform(
-          SVGAnimatedTransformList::create(this, SVGNames::transformAttr)) {
+      m_transform(SVGAnimatedTransformList::create(this,
+                                                   SVGNames::transformAttr,
+                                                   CSSPropertyTransform)) {
   addToPropertyMap(m_transform);
 }
 
@@ -108,74 +110,29 @@ SVGMatrixTearOff* SVGGraphicsElement::getScreenCTMFromJavascript() {
   return SVGMatrixTearOff::create(getScreenCTM());
 }
 
-bool SVGGraphicsElement::hasAnimatedLocalTransform() const {
-  const ComputedStyle* style =
-      layoutObject() ? layoutObject()->style() : nullptr;
+void SVGGraphicsElement::collectStyleForPresentationAttribute(
+    const QualifiedName& name,
+    const AtomicString& value,
+    MutableStylePropertySet* style) {
+  if (name == SVGNames::transformAttr) {
+    addPropertyToPresentationAttributeStyle(
+        style, CSSPropertyTransform, m_transform->currentValue()->cssValue());
+    return;
+  }
+  SVGElement::collectStyleForPresentationAttribute(name, value, style);
+}
 
+bool SVGGraphicsElement::hasAnimatedLocalTransform() const {
   // Each of these is used in
   // SVGGraphicsElement::calculateAnimatedLocalTransform to create an animated
   // local transform.
-  return (style && style->hasTransform()) ||
-         !m_transform->currentValue()->isEmpty() || hasSVGRareData();
+  return hasTransform() || hasSVGRareData();
 }
 
 AffineTransform SVGGraphicsElement::calculateAnimatedLocalTransform() const {
-  AffineTransform matrix;
-  const ComputedStyle* style =
-      layoutObject() ? layoutObject()->style() : nullptr;
-
-  // If CSS property was set, use that, otherwise fallback to attribute (if
-  // set).
-  if (style && style->hasTransform()) {
-    TransformationMatrix transform;
-    float zoom = style->effectiveZoom();
-
-    // SVGTextElements need special handling for the text positioning code.
-    if (isSVGTextElement(this)) {
-      // Do not take into account SVG's zoom rules, transform-origin, or
-      // percentage values.
-      style->applyTransform(
-          transform, LayoutSize(0, 0), ComputedStyle::ExcludeTransformOrigin,
-          ComputedStyle::IncludeMotionPath,
-          ComputedStyle::IncludeIndependentTransformProperties);
-    } else {
-      // 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 = layoutObject()->objectBoundingBox();
-        scaledBBox.scale(zoom);
-        transform.scale(1 / zoom);
-        style->applyTransform(
-            transform, scaledBBox, ComputedStyle::IncludeTransformOrigin,
-            ComputedStyle::IncludeMotionPath,
-            ComputedStyle::IncludeIndependentTransformProperties);
-        transform.scale(zoom);
-      } else {
-        style->applyTransform(
-            transform, layoutObject()->objectBoundingBox(),
-            ComputedStyle::IncludeTransformOrigin,
-            ComputedStyle::IncludeMotionPath,
-            ComputedStyle::IncludeIndependentTransformProperties);
-      }
-    }
-
-    // Flatten any 3D transform.
-    matrix = transform.toAffineTransform();
-  } else {
-    m_transform->currentValue()->concatenate(matrix);
-  }
-
+  AffineTransform matrix = calculateTransform();
   if (hasSVGRareData())
-    return *svgRareData()->animateMotionTransform() * matrix;
+    matrix.preMultiply(*svgRareData()->animateMotionTransform());
   return matrix;
 }
 
@@ -197,8 +154,15 @@ void SVGGraphicsElement::svgAttributeChanged(const QualifiedName& attrName) {
     if (!object)
       return;
 
+    invalidateSVGPresentationAttributeStyle();
+
     SVGElement::InvalidationGuard invalidationGuard(this);
-    object->setNeedsTransformUpdate();
+    // TODO(fs): The InvalidationGuard will make sure all instances are
+    // invalidated, but the style recalc will propagate to instances too. So
+    // there is some redundant operations being performed here. Could we get
+    // away with removing the InvalidationGuard?
+    setNeedsStyleRecalc(LocalStyleChange,
+                        StyleChangeReasonForTracing::fromAttribute(attrName));
     markForLayoutAndParentResourceInvalidation(object);
     return;
   }