Get rid of Reset and ResetStyleResolverAndFontSelector.

Source/core/dom/StyleSheetCollection.cpp

Index: Source/core/dom/StyleSheetCollection.cpp
diff --git a/Source/core/dom/StyleSheetCollection.cpp b/Source/core/dom/StyleSheetCollection.cpp
index 03e6611bddd5076581ea98d83102ea1a710772f2..c25f30e12ecf86a52a5ac4b6f91a970a2b99e65f 100644
--- a/Source/core/dom/StyleSheetCollection.cpp
+++ b/Source/core/dom/StyleSheetCollection.cpp
@@ -133,7 +133,7 @@ StyleSheetCollection::StyleResolverUpdateType StyleSheetCollection::compareStyle
     }
     // If all new sheets were added at the end of the list we can just add them to existing StyleResolver.
     // If there were insertions we need to re-add all the stylesheets so rules are ordered correctly.
-    return hasInsertions ? Reset : Additive;
+    return hasInsertions ? Reconstruct : Additive;
 }
 
 bool StyleSheetCollection::activeLoadingStyleSheetLoaded(const Vector<RefPtr<CSSStyleSheet> >& newStyleSheets)
@@ -153,26 +153,6 @@ bool StyleSheetCollection::activeLoadingStyleSheetLoaded(const Vector<RefPtr<CSS
     return false;
 }
 
-static bool styleSheetContentsHasFontFaceRule(Vector<StyleSheetContents*> sheets)
-{
-    for (unsigned i = 0; i < sheets.size(); ++i) {
-        ASSERT(sheets[i]);
-        if (sheets[i]->hasFontFaceRule())
-            return true;
-    }
-    return false;
-}
-
-static bool cssStyleSheetHasFontFaceRule(const Vector<RefPtr<CSSStyleSheet> > sheets)
-{
-    for (unsigned i = 0; i < sheets.size(); ++i) {
-        ASSERT(sheets[i]);
-        if (sheets[i]->contents()->hasFontFaceRule())
-            return true;
-    }
-    return false;
-}
-
 void StyleSheetCollection::analyzeStyleSheetChange(StyleResolverUpdateMode updateMode, const StyleSheetCollectionBase& newCollection, StyleSheetChange& change)
 {
     if (activeLoadingStyleSheetLoaded(newCollection.activeAuthorStyleSheets()))
@@ -183,31 +163,10 @@ void StyleSheetCollection::analyzeStyleSheetChange(StyleResolverUpdateMode updat
 
     // Find out which stylesheets are new.
     Vector<StyleSheetContents*> addedSheets;
-    if (m_activeAuthorStyleSheets.size() <= newCollection.activeAuthorStyleSheets().size()) {
+    if (m_activeAuthorStyleSheets.size() <= newCollection.activeAuthorStyleSheets().size())
         change.styleResolverUpdateType = compareStyleSheets(m_activeAuthorStyleSheets, newCollection.activeAuthorStyleSheets(), addedSheets);
-    } else {
-        StyleResolverUpdateType updateType = compareStyleSheets(newCollection.activeAuthorStyleSheets(), m_activeAuthorStyleSheets, addedSheets);
-        if (updateType != Additive) {
-            change.styleResolverUpdateType = updateType;
-        } else {
-            if (styleSheetContentsHasFontFaceRule(addedSheets)) {
-                change.styleResolverUpdateType = ResetStyleResolverAndFontSelector;
-                return;
-            }
-            // FIXME: since currently all stylesheets are re-added after reseting styleresolver,
-            // fontSelector should be always reset. After creating RuleSet for each StyleSheetContents,
-            // we can avoid appending all stylesheetcontents in reset case.
-            // So we can remove "styleSheetContentsHasFontFaceRule(newSheets)".
-            if (cssStyleSheetHasFontFaceRule(newCollection.activeAuthorStyleSheets()))
-                change.styleResolverUpdateType = ResetStyleResolverAndFontSelector;
-            else
-                change.styleResolverUpdateType = Reset;
-        }
-    }
-
-    // FIXME: If styleResolverUpdateType is Reconstruct, we should return early here since
-    // we need to recalc the whole document. It's wrong to use StyleInvalidationAnalysis since
-    // it only looks at the addedSheets.
+    else
+        compareStyleSheets(newCollection.activeAuthorStyleSheets(), m_activeAuthorStyleSheets, addedSheets);
 
     // If we are already parsing the body and so may have significant amount of elements, put some effort into trying to avoid style recalcs.
     if (!document()->body() || document()->hasNodesWithPlaceholderStyle())
@@ -229,20 +188,6 @@ void StyleSheetCollection::clearMediaQueryRuleSetStyleSheets()
     }
 }
 
-void StyleSheetCollection::resetAllRuleSetsInTreeScope(StyleResolver* styleResolver)
-{
-    // FIXME: If many web developers use style scoped, implement reset RuleSets in per-scoping node manner.
-    if (DocumentOrderedList* styleScopedScopingNodes = scopingNodesForStyleScoped()) {
-        for (DocumentOrderedList::iterator it = styleScopedScopingNodes->begin(); it != styleScopedScopingNodes->end(); ++it)
-            styleResolver->resetAuthorStyle(toContainerNode(*it));
-    }
-    if (ListHashSet<Node*, 4>* removedNodes = scopingNodesRemoved()) {
-        for (ListHashSet<Node*, 4>::iterator it = removedNodes->begin(); it != removedNodes->end(); ++it)
-            styleResolver->resetAuthorStyle(toContainerNode(*it));
-    }
-    styleResolver->resetAuthorStyle(toContainerNode(m_treeScope.rootNode()));
-}
-
 static bool styleSheetsUseRemUnits(const Vector<RefPtr<CSSStyleSheet> >& sheets)
 {
     for (unsigned i = 0; i < sheets.size(); ++i) {
@@ -257,4 +202,29 @@ void StyleSheetCollection::updateUsesRemUnits()
     m_usesRemUnits = styleSheetsUseRemUnits(m_activeAuthorStyleSheets);
 }
 
+bool StyleSheetCollection::updateActiveStyleSheets(StyleEngine* engine, StyleResolverUpdateMode updateMode)
+{
+    StyleSheetCollectionBase collection;
+    collectStyleSheets(engine, collection);
+
+    StyleSheetChange change;
+    analyzeStyleSheetChange(updateMode, collection, change);
+
+    if (change.styleResolverUpdateType == Reconstruct) {
+        engine->clearResolver();
+    } else if (StyleResolver* styleResolver = engine->resolverIfExists()) {
+        ASSERT(change.styleResolverUpdateType == Additive);
+        // 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);
+        styleResolver->lazyAppendAuthorStyleSheets(m_activeAuthorStyleSheets.size(), collection.activeAuthorStyleSheets());
+    }
+
+    m_scopingNodesForStyleScoped.didRemoveScopingNodes();
+    collection.swap(*this);
+    updateUsesRemUnits();
+
+    return change.requiresFullStyleRecalc;
+}
+
 }