[GeometryInterface] add getBounds function in DOMQaud.

third_party/WebKit/Source/core/dom/DOMQuad.h

 // Copyright 2017 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 DOMQuad_h
 #define DOMQuad_h
 
 #include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/CoreExport.h"
 
 namespace blink {
 
 class DOMPoint;
 class DOMPointInit;
 class DOMQuadInit;
+class DOMRect;
 class DOMRectInit;
 
 class CORE_EXPORT DOMQuad : public GarbageCollected<DOMQuad>,
                             public ScriptWrappable {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   static DOMQuad* create(const DOMPointInit& p1,
                          const DOMPointInit& p2,
                          const DOMPointInit& p3,
                          const DOMPointInit& p4);
   static DOMQuad* fromRect(const DOMRectInit&);
   static DOMQuad* fromQuad(const DOMQuadInit&);
 
   DOMPoint* p1() const { return m_p1; }
   DOMPoint* p2() const { return m_p2; }
   DOMPoint* p3() const { return m_p3; }
   DOMPoint* p4() const { return m_p4; }
 
+  DOMRect* getBounds();
+
   ScriptValue toJSONForBinding(ScriptState*) const;
 
   DEFINE_INLINE_TRACE() {
     visitor->trace(m_p1);
     visitor->trace(m_p2);
     visitor->trace(m_p3);
     visitor->trace(m_p4);
   }
 
  private:
   DOMQuad(const DOMPointInit& p1,
           const DOMPointInit& p2,
           const DOMPointInit& p3,
           const DOMPointInit& p4);
   DOMQuad(double x, double y, double width, double height);
 
+  void calculateBounds();
+
   Member<DOMPoint> m_p1;
   Member<DOMPoint> m_p2;
   Member<DOMPoint> m_p3;
   Member<DOMPoint> m_p4;
+
+  double m_left;
+  double m_right;
+  double m_top;
+  double m_bottom;
 };
 
 }  // namespace blink
 
 #endif