Implement matching part of ::slotted() pseudo element

third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp

Index: third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp
diff --git a/third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp b/third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp
index 0f993d87aea9d8f88aac90c8dc41b76c2ed396b3..ddec3539d07e4b6ef4fc3163a375f6c05ab3cb94 100644
--- a/third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp
+++ b/third_party/WebKit/Source/core/css/resolver/SharedStyleFinder.cpp
@@ -278,6 +278,11 @@ bool SharedStyleFinder::canShareStyleWithElement(Element& candidate) const
             return false;
     }
 
+    // TODO(kochi): Write equivalent of sharingCandidateDistributedToSameInsertionPoint()
+    // for slotted elements.
+    if (element().assignedSlotForBinding())
+        return false;
+
     return true;
 }