[GeometryInterface] add getBounds function in DOMQaud.

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

Index: third_party/WebKit/Source/core/dom/DOMQuad.cpp
diff --git a/third_party/WebKit/Source/core/dom/DOMQuad.cpp b/third_party/WebKit/Source/core/dom/DOMQuad.cpp
index 853e0740e2a90328592cd8861bfa1fd13b31987e..2bf2de0b22388b8346830216502e1f84a5f1fd88 100644
--- a/third_party/WebKit/Source/core/dom/DOMQuad.cpp
+++ b/third_party/WebKit/Source/core/dom/DOMQuad.cpp
@@ -7,6 +7,7 @@
 #include "bindings/core/v8/V8ObjectBuilder.h"
 #include "core/dom/DOMPoint.h"
 #include "core/dom/DOMQuadInit.h"
+#include "core/dom/DOMRect.h"
 #include "core/dom/DOMRectInit.h"
 
 namespace blink {
@@ -29,6 +30,25 @@ DOMQuad* DOMQuad::fromQuad(const DOMQuadInit& other) {
                      other.hasP3() ? other.p4() : DOMPointInit());
 }
 
+DOMRect* DOMQuad::getBounds() {
+  return DOMRect::create(m_left, m_top, m_right - m_left, m_bottom - m_top);
+}
+
+void DOMQuad::calculateBounds() {
+  m_left = std::min(p1()->x(), p2()->x());
+  m_left = std::min(m_left, p3()->x());
+  m_left = std::min(m_left, p4()->x());
+  m_top = std::min(p1()->y(), p2()->y());
+  m_top = std::min(m_top, p3()->y());
+  m_top = std::min(m_top, p4()->y());
+  m_right = std::max(p1()->x(), p2()->x());
+  m_right = std::max(m_right, p3()->x());
+  m_right = std::max(m_right, p4()->x());
+  m_bottom = std::max(p1()->y(), p2()->y());
+  m_bottom = std::max(m_bottom, p3()->y());
+  m_bottom = std::max(m_bottom, p4()->y());
+}
+
 DOMQuad::DOMQuad(const DOMPointInit& p1,
                  const DOMPointInit& p2,
                  const DOMPointInit& p3,
@@ -36,13 +56,17 @@ DOMQuad::DOMQuad(const DOMPointInit& p1,
     : m_p1(DOMPoint::fromPoint(p1)),
       m_p2(DOMPoint::fromPoint(p2)),
       m_p3(DOMPoint::fromPoint(p3)),
-      m_p4(DOMPoint::fromPoint(p4)) {}
+      m_p4(DOMPoint::fromPoint(p4)) {
+  calculateBounds();
+}
 
 DOMQuad::DOMQuad(double x, double y, double width, double height)
     : m_p1(DOMPoint::create(x, y, 0, 1)),
       m_p2(DOMPoint::create(x + width, y, 0, 1)),
       m_p3(DOMPoint::create(x + width, y + height, 0, 1)),
-      m_p4(DOMPoint::create(x, y + height, 0, 1)) {}
+      m_p4(DOMPoint::create(x, y + height, 0, 1)) {
+  calculateBounds();
+}
 
 ScriptValue DOMQuad::toJSONForBinding(ScriptState* scriptState) const {
   V8ObjectBuilder result(scriptState);