Add CSS support for Containment

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index 43ca7e6f9bbb99b9699b3b314fb8cb23c2a066c2..4d81f2d51545d0fb68dc746d4e443d4ba331d7bd 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -821,6 +821,8 @@ public:
     // through their self-painting layers. So the layout code doesn't account for them.
     bool hasVisualOverflowingEffect() const { return boxShadow() || hasBorderImageOutsets() || hasOutline(); }
 
+    Containment contain() const { return static_cast<Containment>(rareNonInheritedData->m_contain); }
+
     EBoxSizing boxSizing() const { return m_box->boxSizing(); }
     EUserModify userModify() const { return static_cast<EUserModify>(rareInheritedData->userModify); }
     EUserDrag userDrag() const { return static_cast<EUserDrag>(rareNonInheritedData->userDrag); }
@@ -1304,6 +1306,7 @@ public:
     void setBoxShadow(PassRefPtr<ShadowList>);
     void setBoxReflect(PassRefPtr<StyleReflection> reflect) { if (rareNonInheritedData->m_boxReflect != reflect) rareNonInheritedData.access()->m_boxReflect = reflect; }
     void setBoxSizing(EBoxSizing s) { SET_VAR(m_box, m_boxSizing, s); }
+    void setContain(Containment contain) { SET_VAR(rareNonInheritedData, m_contain, contain); }
     void setFlexGrow(float f) { SET_VAR(rareNonInheritedData.access()->m_flexibleBox, m_flexGrow, f); }
     void setFlexShrink(float f) { SET_VAR(rareNonInheritedData.access()->m_flexibleBox, m_flexShrink, f); }
     void setFlexBasis(const Length& length) { SET_VAR(rareNonInheritedData.access()->m_flexibleBox, m_flexBasis, length); }
@@ -1623,6 +1626,7 @@ public:
     static ECaptionSide initialCaptionSide() { return CAPTOP; }
     static EClear initialClear() { return CNONE; }
     static LengthBox initialClip() { return LengthBox(); }
+    static Containment initialContain() { return ContainsNone; }
     static TextDirection initialDirection() { return LTR; }
     static WritingMode initialWritingMode() { return TopToBottomWritingMode; }
     static TextCombine initialTextCombine() { return TextCombineNone; }