| Index: third_party/WebKit/Source/core/css/invalidation/InvalidationSet.cpp
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| diff --git a/third_party/WebKit/Source/core/css/invalidation/InvalidationSet.cpp b/third_party/WebKit/Source/core/css/invalidation/InvalidationSet.cpp
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| index f9750d938fd5ac56c5c8f26f1c39b7bdda6109cb..a324786050cf826b56b2610f37580376bd5444c1 100644
 | 
| --- a/third_party/WebKit/Source/core/css/invalidation/InvalidationSet.cpp
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| +++ b/third_party/WebKit/Source/core/css/invalidation/InvalidationSet.cpp
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| @@ -269,4 +269,18 @@ void InvalidationSet::show() const
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|  }
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|  #endif // NDEBUG
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|  
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| +SiblingInvalidationSet::SiblingInvalidationSet()
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| +    : m_maxDirectAdjacentSelectors(1)
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| +    , m_descendantInvalidationSet(DescendantInvalidationSet::create())
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| +{
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| +}
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| +
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| +void SiblingInvalidationSet::combine(const SiblingInvalidationSet& other)
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| +{
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| +    m_maxDirectAdjacentSelectors = std::max(m_maxDirectAdjacentSelectors, other.m_maxDirectAdjacentSelectors);
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| +    m_descendantInvalidationSet->combine(other.descendants());
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| +
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| +    InvalidationSet::combine(other);
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| +}
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| +
 | 
|  } // namespace blink
 | 
| 
 |