[Typed OM] Implement CSSValue->CSSRotation conversion

third_party/WebKit/Source/core/css/cssom/CSSRotation.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CSSRotation_h
 #define CSSRotation_h
 
 #include "core/css/cssom/CSSAngleValue.h"
 #include "core/css/cssom/CSSMatrixTransformComponent.h"
 #include "core/css/cssom/TransformComponent.h"
@@ skipping 17 matching lines @@
     static CSSRotation* create(double x, double y, double z, double angle)
     {
         return new CSSRotation(x, y, z, angle);
     }
 
     static CSSRotation* create(double x, double y, double z, const CSSAngleValue* angleValue)
     {
         return new CSSRotation(x, y, z, angleValue->degrees());
     }
 
-    static CSSRotation* fromCSSValue(const CSSFunctionValue&) { return nullptr; }
+    static CSSRotation* fromCSSValue(const CSSFunctionValue&);
 
     double angle() const { return m_angle; }
     double x() const { return m_x; }
     double y() const { return m_y; }
     double z() const { return m_z; }
 
     TransformComponentType type() const override { return m_is2D ? RotationType : Rotation3DType; }
 
     CSSMatrixTransformComponent* asMatrix() const override
     {
@@ skipping 23 matching lines @@
     double m_x;
     double m_y;
     double m_z;
     double m_angle;
     bool m_is2D;
 };
 
 } // namespace blink
 
 #endif