| Index: third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
 | 
| diff --git a/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp b/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
 | 
| index b80fcb869d8d85f524fc2adb4951684aea6834b0..2d99858cd70a50d93294295a234d955d2b1dbba6 100644
 | 
| --- a/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
 | 
| +++ b/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
 | 
| @@ -2833,7 +2833,7 @@ const CSSValue* ComputedStyleCSSValueMapping::get(
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|      case CSSPropertyFontVariantNumeric:
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|        return valueForFontVariantNumeric(style);
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|      case CSSPropertyZIndex:
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| -      if (style.hasAutoZIndex())
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| +      if (style.hasAutoZIndex() || !style.isStackingContext())
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|          return CSSIdentifierValue::create(CSSValueAuto);
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|        return CSSPrimitiveValue::create(style.zIndex(),
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|                                         CSSPrimitiveValue::UnitType::Integer);
 | 
| 
 |