Adding matrixTrasnform to DOMPointReadOnly interfaces as following spec.

third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html

Index: third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html
diff --git a/third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html b/third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html
index 1c0ef51af372df8bb0a97628baff50241830431e..37294532980d38e59d53046aa87773ecb0febbfa 100644
--- a/third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html
+++ b/third_party/WebKit/LayoutTests/fast/dom/geometry-interfaces-dom-point-readonly.html
@@ -9,6 +9,26 @@
 'use strict';
 
 test(() => {
+  var point = new DOMPointReadOnly();
+  assert_dom_point_equals(point, [0, 0, 0, 1]);
+}, 'DOMPointReadOnly constructor without parameter');
+
+test(() => {
+  var point = new DOMPointReadOnly(10);
+  assert_dom_point_equals(point, [10, 0, 0, 1]);
+}, 'DOMPointReadOnly constructor with x parameter');
+
+test(() => {
+  var point = new DOMPointReadOnly(10, 20);
+  assert_dom_point_equals(point, [10, 20, 0, 1]);
+}, 'DOMPointReadOnly constructor with x, y parameters');
+
+test(() => {
+  var point = new DOMPointReadOnly(10, 20, 30);
+  assert_dom_point_equals(point, [10, 20, 30, 1]);
+}, 'DOMPointReadOnly constructor with x, y, z parameters');
+
+test(() => {
   var point = new DOMPointReadOnly(10, 20, 30, 40);
   assert_dom_point_equals(point, [10, 20, 30, 40]);
 }, 'DOMPointReadOnly constructor with x, y, z, w parameters');
@@ -40,10 +60,19 @@ test(() => {
   var point1 = DOMPointReadOnly.fromPoint();
   var point2 = DOMPointReadOnly.fromPoint();
   assert_false(point1 == point2);
-  assert_true(point1.x == point2.x);
-  assert_true(point1.y == point2.y);
-  assert_true(point1.z == point2.z);
-  assert_true(point1.w == point2.w);
+  assert_dom_point_equals(point1, point2);
 }, 'DOMPointReadOnly.fromPoint() should create a new DOMPointReadOnly');
 
+test(() => {
+  var point = new DOMPointReadOnly(5, 4);
+  var transformed_point = point.matrixTransform(new DOMMatrixReadOnly([2, 0, 0, 2, 10, 10]));
+  assert_dom_point_equals(transformed_point, new DOMPoint(20, 18));
+}, 'DOMMatrixReadOnly.matrixTransform() - 2d matrixTransform');
+
+test(() => {
+  var point = new DOMPointReadOnly(5, 4);
+  var transformed_point = point.matrixTransform(new DOMMatrixReadOnly([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]));
+  assert_dom_point_equals(transformed_point, new DOMPoint(38, 48, 58, 68));
+}, 'DOMMatrixReadOnly.matrixTransform() - 3d matrixTransform');
+
 </script>