Do refactor in collectGradientAttributes() and renderStyleForLengthResolve()

Source/core/svg/SVGLinearGradientElement.cpp

Index: Source/core/svg/SVGLinearGradientElement.cpp
diff --git a/Source/core/svg/SVGLinearGradientElement.cpp b/Source/core/svg/SVGLinearGradientElement.cpp
index 19df4d50b46b7eedc0f0ac5a5057ca7f93c6c38b..8a596e44944328a425c13512bd5d2d1486448084 100644
--- a/Source/core/svg/SVGLinearGradientElement.cpp
+++ b/Source/core/svg/SVGLinearGradientElement.cpp
@@ -115,70 +115,76 @@ RenderObject* SVGLinearGradientElement::createRenderer(RenderStyle*)
     return new RenderSVGResourceLinearGradient(this);
 }
 
-bool SVGLinearGradientElement::collectGradientAttributes(LinearGradientAttributes& attributes)
+static void setGradientAttributes(SVGGradientElement* element, LinearGradientAttributes& attributes, bool isLinear = true)
 {
-    HashSet<SVGGradientElement*> processedGradients;
+    if (!attributes.hasSpreadMethod() && element->hasAttribute(SVGNames::spreadMethodAttr))
+        attributes.setSpreadMethod(element->spreadMethodCurrentValue());
 
-    bool isLinear = true;
-    SVGGradientElement* current = this;
+    if (!attributes.hasGradientUnits() && element->hasAttribute(SVGNames::gradientUnitsAttr))
+        attributes.setGradientUnits(element->gradientUnitsCurrentValue());
 
-    while (current) {
-        if (!current->renderer())
-            return false;
-
-        if (!attributes.hasSpreadMethod() && current->hasAttribute(SVGNames::spreadMethodAttr))
-            attributes.setSpreadMethod(current->spreadMethodCurrentValue());
+    if (!attributes.hasGradientTransform() && element->hasAttribute(SVGNames::gradientTransformAttr)) {
+        AffineTransform transform;
+        element->gradientTransformCurrentValue().concatenate(transform);
+        attributes.setGradientTransform(transform);
+    }
 
-        if (!attributes.hasGradientUnits() && current->hasAttribute(SVGNames::gradientUnitsAttr))
-            attributes.setGradientUnits(current->gradientUnitsCurrentValue());
+    if (!attributes.hasStops()) {
+        const Vector<Gradient::ColorStop>& stops(element->buildStops());
+        if (!stops.isEmpty())
+            attributes.setStops(stops);
+    }
 
-        if (!attributes.hasGradientTransform() && current->hasAttribute(SVGNames::gradientTransformAttr)) {
-            AffineTransform transform;
-            current->gradientTransformCurrentValue().concatenate(transform);
-            attributes.setGradientTransform(transform);
-        }
+    if (isLinear) {
+        SVGLinearGradientElement* linear = toSVGLinearGradientElement(element);
 
-        if (!attributes.hasStops()) {
-            const Vector<Gradient::ColorStop>& stops(current->buildStops());
-            if (!stops.isEmpty())
-                attributes.setStops(stops);
-        }
+        if (!attributes.hasX1() && element->hasAttribute(SVGNames::x1Attr))
+            attributes.setX1(linear->x1()->currentValue());
 
-        if (isLinear) {
-            SVGLinearGradientElement* linear = toSVGLinearGradientElement(current);
+        if (!attributes.hasY1() && element->hasAttribute(SVGNames::y1Attr))
+            attributes.setY1(linear->y1()->currentValue());
 
-            if (!attributes.hasX1() && current->hasAttribute(SVGNames::x1Attr))
-                attributes.setX1(linear->x1()->currentValue());
+        if (!attributes.hasX2() && element->hasAttribute(SVGNames::x2Attr))
+            attributes.setX2(linear->x2()->currentValue());
 
-            if (!attributes.hasY1() && current->hasAttribute(SVGNames::y1Attr))
-                attributes.setY1(linear->y1()->currentValue());
+        if (!attributes.hasY2() && element->hasAttribute(SVGNames::y2Attr))
+            attributes.setY2(linear->y2()->currentValue());
+    }
+}
 
-            if (!attributes.hasX2() && current->hasAttribute(SVGNames::x2Attr))
-                attributes.setX2(linear->x2()->currentValue());
+bool SVGLinearGradientElement::collectGradientAttributes(LinearGradientAttributes& attributes)
+{
+    if (!renderer())
+        return false;
 
-            if (!attributes.hasY2() && current->hasAttribute(SVGNames::y2Attr))
-                attributes.setY2(linear->y2()->currentValue());
-        }
+    HashSet<SVGGradientElement*> processedGradients;
+    SVGGradientElement* current = this;
 
-        processedGradients.add(current);
+    setGradientAttributes(current, attributes);
+    processedGradients.add(current);
 
+    while (true) {
         // Respect xlink:href, take attributes from referenced element
         Node* refNode = SVGURIReference::targetElementFromIRIString(current->hrefCurrentValue(), document());
-        if (refNode && (refNode->hasTagName(SVGNames::linearGradientTag) || refNode->hasTagName(SVGNames::radialGradientTag))) {
+        if (refNode && isSVGGradientElement(*refNode)) {
             current = toSVGGradientElement(refNode);
 
             // Cycle detection
-            if (processedGradients.contains(current)) {
-                current = 0;
-                break;
-            }
-
-            isLinear = current->hasTagName(SVGNames::linearGradientTag);
-        } else
-            current = 0;
+            if (processedGradients.contains(current))
+                return true;
+
+            if (!current->renderer())
+                return false;
+
+            setGradientAttributes(current, attributes, current->hasTagName(SVGNames::linearGradientTag));
+            processedGradients.add(current);
+        } else {
+            return true;
+        }
     }
 
-    return true;
+    ASSERT_NOT_REACHED();
+    return false;
 }
 
 bool SVGLinearGradientElement::selfHasRelativeLengths() const