Get rid of Reset and ResetStyleResolverAndFontSelector.

Source/core/dom/ShadowTreeStyleSheetCollection.cpp

Index: Source/core/dom/ShadowTreeStyleSheetCollection.cpp
diff --git a/Source/core/dom/ShadowTreeStyleSheetCollection.cpp b/Source/core/dom/ShadowTreeStyleSheetCollection.cpp
index d0ae20a8a48d64b356f1b9241886591b0c87159c..ac4137c717affb8eca8840748f6010bf7fae862c 100644
--- a/Source/core/dom/ShadowTreeStyleSheetCollection.cpp
+++ b/Source/core/dom/ShadowTreeStyleSheetCollection.cpp
@@ -90,36 +90,4 @@ void ShadowTreeStyleSheetCollection::collectStyleSheets(StyleEngine* engine, Sty
     }
 }
 
-bool ShadowTreeStyleSheetCollection::updateActiveStyleSheets(StyleEngine* engine, StyleResolverUpdateMode updateMode)
-{
-    StyleSheetCollectionBase collection;
-    collectStyleSheets(engine, collection);
-
-    StyleSheetChange change;
-    analyzeStyleSheetChange(updateMode, collection, change);
-
-    if (StyleResolver* styleResolver = engine->resolverIfExists()) {
-        // FIXME: We might have already had styles in child treescope. In this case, we cannot use buildScopedStyleTreeInDocumentOrder.
-        // Need to change "false" to some valid condition.
-        styleResolver->setBuildScopedStyleTreeInDocumentOrder(false);
-        if (change.styleResolverUpdateType != Additive) {
-            // We should not destroy StyleResolver when we find any stylesheet update in a shadow tree.
-            // In this case, we will reset rulesets created from style elements in the shadow tree.
-            resetAllRuleSetsInTreeScope(styleResolver);
-            styleResolver->removePendingAuthorStyleSheets(m_activeAuthorStyleSheets);
-            styleResolver->lazyAppendAuthorStyleSheets(0, collection.activeAuthorStyleSheets());
-        } else {
-            styleResolver->lazyAppendAuthorStyleSheets(m_activeAuthorStyleSheets.size(), collection.activeAuthorStyleSheets());
-        }
-    }
-    if (change.requiresFullStyleRecalc)
-        toShadowRoot(m_treeScope.rootNode())->host()->setNeedsStyleRecalc();
-
-    m_scopingNodesForStyleScoped.didRemoveScopingNodes();
-    collection.swap(*this);
-    updateUsesRemUnits();
-
-    return change.requiresFullStyleRecalc;
-}
-
 }