Adding fromPoint to DOMPoint and DOMPointReadOnly interfaces following spec.

third_party/WebKit/Source/core/dom/DOMPoint.cpp

Index: third_party/WebKit/Source/core/dom/DOMPoint.cpp
diff --git a/third_party/WebKit/Source/core/dom/DOMPoint.cpp b/third_party/WebKit/Source/core/dom/DOMPoint.cpp
index 1bb78667c5dbcac01646d27aae1e2a5c70eddf49..7b97ecff65136d8f22589126faf3bb2ad851259f 100644
--- a/third_party/WebKit/Source/core/dom/DOMPoint.cpp
+++ b/third_party/WebKit/Source/core/dom/DOMPoint.cpp
@@ -16,6 +16,10 @@ DOMPoint* DOMPoint::create(double x, double y, double z, double w) {
   return new DOMPoint(x, y, z, w);
 }
 
+DOMPoint* DOMPoint::fromPoint(DOMPointInit& other) {
+  return new DOMPoint(other.x(), other.y(), other.z(), other.w());
+}
+
 DOMPoint::DOMPoint(double x, double y, double z, double w)
     : DOMPointReadOnly(x, y, z, w) {}