Fix CSS typed OM CSSSkewX and CSSSkewY toMatrix method to use degrees instead of radians.

The toMatrix method of a CSSTransformComponent should return a DOMMatrix
representing the object transformation.
https://www.w3.org/TR/css-typed-om-1/#dom-csstransformcomponent-tomatrix

The skewXSelf and skewYSelf methods used to apply a transformation on a
matrix must be provided with an angle parameter expressed in degrees.
https://www.w3.org/TR/geometry-1/#dom-dommatrix-skewxself
https://www.w3.org/TR/geometry-1/#dom-dommatrix-skewyself

Since the angles passed to the skewXSelf and skewYSelf were in radians,
DOMMatrix returned by the toMatrix method of those two components was incorrect.

R=alancutter@chromium.org

Change-Id: I5edc1cdf1493184584154723508c6e20c212ac92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2242008
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Reviewed-by: Alan Cutter <alancutter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#786632}

AUTHORS

@@ -183,6 +183,7 @@ Changwan Hong <changwan.hong@navercorp.com>
 Changyeon Kim <cyzero.kim@samsung.com>
 Chanho Park <parkch98@gmail.com>
 Chansik Yun <chansik.yun@gmail.com>
+Chany Arpin-Plante <chany.arpin@gmail.com>
 Chaobin Zhang <zhchbin@gmail.com>
 Charles Vaughn <cvaughn@gmail.com>
 Cheng Zhao <zcbenz@gmail.com>

third_party/blink/renderer/core/css/cssom/css_skew_x.cc

@@ -52,7 +52,7 @@ CSSSkewX* CSSSkewX::FromCSSValue(const CSSFunctionValue& value) {
 }
 
 DOMMatrix* CSSSkewX::toMatrix(ExceptionState&) const {
-  CSSUnitValue* ax = ax_->to(CSSPrimitiveValue::UnitType::kRadians);
+  CSSUnitValue* ax = ax_->to(CSSPrimitiveValue::UnitType::kDegrees);
   DCHECK(ax);
   DOMMatrix* result = DOMMatrix::Create();
   result->skewXSelf(ax->value());

third_party/blink/renderer/core/css/cssom/css_skew_y.cc

@@ -52,7 +52,7 @@ CSSSkewY* CSSSkewY::FromCSSValue(const CSSFunctionValue& value) {
 }
 
 DOMMatrix* CSSSkewY::toMatrix(ExceptionState&) const {
-  CSSUnitValue* ay = ay_->to(CSSPrimitiveValue::UnitType::kRadians);
+  CSSUnitValue* ay = ay_->to(CSSPrimitiveValue::UnitType::kDegrees);
   DCHECK(ay);
   DOMMatrix* result = DOMMatrix::Create();
   result->skewYSelf(ay->value());

third_party/blink/web_tests/external/wpt/css/css-typed-om/stylevalue-subclasses/cssTransformComponent-toMatrix.html

@@ -51,7 +51,7 @@ test(() => {
 
 test(() => {
   const component = new CSSSkewX(
-    new CSSUnitValue(10, 'rad'),
+    new CSSUnitValue(10, 'deg'),
   );
   const expectedMatrix = (new DOMMatrixReadOnly()).skewX(10);
   assert_matrix_approx_equals(component.toMatrix(), expectedMatrix, gEpsilon);
@@ -59,7 +59,7 @@ test(() => {
 
 test(() => {
   const component = new CSSSkewY(
-    new CSSUnitValue(10, 'rad'),
+    new CSSUnitValue(10, 'deg'),
   );
   const expectedMatrix = (new DOMMatrixReadOnly()).skewY(10);
   assert_matrix_approx_equals(component.toMatrix(), expectedMatrix, gEpsilon);