[SVGDom] Linear gradient 'gradientTransform' support

experimental/svg/model/SkSVGLinearGradient.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGradientShader.h"
 #include "SkSVGLinearGradient.h"
 #include "SkSVGRenderContext.h"
 #include "SkSVGStop.h"
 #include "SkSVGValue.h"
 
 SkSVGLinearGradient::SkSVGLinearGradient() : INHERITED(SkSVGTag::kLinearGradient) {}
 
 void SkSVGLinearGradient::setHref(const SkSVGStringType& href) {
     fHref = std::move(href);
 }
 
+void SkSVGLinearGradient::setGradientTransform(const SkSVGTransformType& t) {
+    fGradientTransform = t;
+}
+
 void SkSVGLinearGradient::setSpreadMethod(const SkSVGSpreadMethod& spread) {
     fSpreadMethod = spread;
 }
 
 void SkSVGLinearGradient::setX1(const SkSVGLength& x1) {
     fX1 = x1;
 }
 
 void SkSVGLinearGradient::setY1(const SkSVGLength& y1) {
     fY1 = y1;
 }
 
 void SkSVGLinearGradient::setX2(const SkSVGLength& x2) {
     fX2 = x2;
 }
 
 void SkSVGLinearGradient::setY2(const SkSVGLength& y2) {
     fY2 = y2;
 }
 
 void SkSVGLinearGradient::onSetAttribute(SkSVGAttribute attr, const SkSVGValue& v) {
     switch (attr) {
+    case SkSVGAttribute::kGradientTransform:
+        if (const auto* t = v.as<SkSVGTransformValue>()) {
+            this->setGradientTransform(*t);
+        }
+        break;
     case SkSVGAttribute::kHref:
         if (const auto* href = v.as<SkSVGStringValue>()) {
             this->setHref(*href);
         }
         break;
     case SkSVGAttribute::kSpreadMethod:
         if (const auto* spread = v.as<SkSVGSpreadMethodValue>()) {
             this->setSpreadMethod(*spread);
         }
         break;
@@ skipping 71 matching lines @@
 
     static_assert(static_cast<SkShader::TileMode>(SkSVGSpreadMethod::Type::kPad) ==
                   SkShader::kClamp_TileMode, "SkSVGSpreadMethod::Type is out of sync");
     static_assert(static_cast<SkShader::TileMode>(SkSVGSpreadMethod::Type::kRepeat) ==
                   SkShader::kRepeat_TileMode, "SkSVGSpreadMethod::Type is out of sync");
     static_assert(static_cast<SkShader::TileMode>(SkSVGSpreadMethod::Type::kReflect) ==
                   SkShader::kMirror_TileMode, "SkSVGSpreadMethod::Type is out of sync");
     const auto tileMode = static_cast<SkShader::TileMode>(fSpreadMethod.type());
 
     paint->setShader(SkGradientShader::MakeLinear(pts, colors.begin(), pos.begin(), colors.count(),
-                                                  tileMode));
+                                                  tileMode, 0, &fGradientTransform.value()));
     return true;
 }