Adding @keyframes rules only affects TreeScope plus host.

third_party/WebKit/Source/core/css/invalidation/StyleSheetInvalidationAnalysis.cpp

 /*
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 10 matching lines @@
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/css/invalidation/StyleSheetInvalidationAnalysis.h"
 
 #include "core/css/CSSSelectorList.h"
 #include "core/css/StyleRuleImport.h"
 #include "core/css/StyleSheetContents.h"
+#include "core/css/resolver/ScopedStyleResolver.h"
 #include "core/dom/ContainerNode.h"
 #include "core/dom/Document.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/StyleChangeReason.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/TreeScope.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/html/HTMLStyleElement.h"
 
 namespace blink {
@@ skipping 118 matching lines @@
             return true;
     }
     return false;
 }
 
 void StyleSheetInvalidationAnalysis::invalidateStyle()
 {
     ASSERT(!m_dirtiesAllStyle);
 
     if (m_addsKeyframes)
-        m_treeScope->document().styleEngine().keyframesRulesAdded();
+        ScopedStyleResolver::keyframesRulesAdded(*m_treeScope);
 
     if (m_treeScope->rootNode().isShadowRoot()) {
         ContainerNode& shadowHost = toShadowRoot(m_treeScope->rootNode()).host();
         shadowHost.setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleSheetChange));
         return;
     }
 
     if (m_idScopes.isEmpty() && m_classScopes.isEmpty())
         return;
     Element* element = ElementTraversal::firstWithin(m_treeScope->document());
     while (element) {
         if (elementMatchesSelectorScopes(element, m_idScopes, m_classScopes)) {
             element->setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::StyleSheetChange));
             // The whole subtree is now invalidated, we can skip to the next sibling.
             element = ElementTraversal::nextSkippingChildren(*element);
             continue;
         }
         element = ElementTraversal::next(*element);
     }
 }
 
 } // namespace blink