Drop InvalidationSetMode.

Source/core/css/RuleFeature.cpp

Index: Source/core/css/RuleFeature.cpp
diff --git a/Source/core/css/RuleFeature.cpp b/Source/core/css/RuleFeature.cpp
index 250988215f7eec346be477df3f55375af0de70d8..0d9b6424a82810f9838d6ad7c85acab6b9feb738 100644
--- a/Source/core/css/RuleFeature.cpp
+++ b/Source/core/css/RuleFeature.cpp
@@ -37,32 +37,39 @@
 #include "core/css/invalidation/DescendantInvalidationSet.h"
 #include "core/dom/Element.h"
 #include "core/dom/Node.h"
-#include "platform/RuntimeEnabledFeatures.h"
 #include "wtf/BitVector.h"
 
 namespace blink {
 
-static bool isSkippableComponentForInvalidation(const CSSSelector& selector)
+static void assertSupportedMatch(CSSSelector::Match match)
 {
-    if (selector.match() == CSSSelector::Tag) {
-        ASSERT(selector.tagQName().localName() == starAtom);
-        return true;
-    }
-    if (selector.match() == CSSSelector::PseudoElement) {
-        switch (selector.pseudoType()) {
-        case CSSSelector::PseudoBefore:
-        case CSSSelector::PseudoAfter:
-        case CSSSelector::PseudoBackdrop:
-        case CSSSelector::PseudoShadow:
-            return true;
-        default:
-            ASSERT(!selector.isCustomPseudoElement());
-            return false;
-        }
+    switch (match) {
+    case CSSSelector::Tag:
+    case CSSSelector::Id:
+    case CSSSelector::Class:
+    case CSSSelector::AttributeExact:
+    case CSSSelector::AttributeSet:
+    case CSSSelector::AttributeHyphen:
+    case CSSSelector::AttributeList:
+    case CSSSelector::AttributeContain:
+    case CSSSelector::AttributeBegin:
+    case CSSSelector::AttributeEnd:
+        break;
+    case CSSSelector::Unknown:
+    case CSSSelector::PagePseudoClass:
+        // These should not appear in StyleRule selectors.
+        ASSERT_NOT_REACHED();
+        break;
+    default:
+        // New match type added. Figure out if it needs a subtree recalc or not.
+        ASSERT_NOT_REACHED();
+        break;
     }
-    if (selector.match() != CSSSelector::PseudoClass)
-        return false;
-    switch (selector.pseudoType()) {
+}
+
+static void assertSupportedPseudo(CSSSelector::PseudoType type)
+{
+    switch (type) {
     case CSSSelector::PseudoEmpty:
     case CSSSelector::PseudoFirstChild:
     case CSSSelector::PseudoFirstOfType:
@@ -76,6 +83,7 @@ static bool isSkippableComponentForInvalidation(const CSSSelector& selector)
     case CSSSelector::PseudoNthLastOfType:
     case CSSSelector::PseudoLink:
     case CSSSelector::PseudoVisited:
+    case CSSSelector::PseudoAny:
     case CSSSelector::PseudoAnyLink:
     case CSSSelector::PseudoHover:
     case CSSSelector::PseudoDrag:
@@ -93,15 +101,90 @@ static bool isSkippableComponentForInvalidation(const CSSSelector& selector)
     case CSSSelector::PseudoInvalid:
     case CSSSelector::PseudoIndeterminate:
     case CSSSelector::PseudoTarget:
+    case CSSSelector::PseudoBefore:
+    case CSSSelector::PseudoAfter:
+    case CSSSelector::PseudoBackdrop:
     case CSSSelector::PseudoLang:
+    case CSSSelector::PseudoNot:
     case CSSSelector::PseudoRoot:
     case CSSSelector::PseudoScope:
     case CSSSelector::PseudoInRange:
     case CSSSelector::PseudoOutOfRange:
+    case CSSSelector::PseudoUserAgentCustomElement:
+    case CSSSelector::PseudoWebKitCustomElement:
     case CSSSelector::PseudoUnresolved:
+    case CSSSelector::PseudoHost:
+    case CSSSelector::PseudoShadow:
     case CSSSelector::PseudoListBox:
+    case CSSSelector::PseudoAutofill:
+    case CSSSelector::PseudoFullPageMedia:
+    case CSSSelector::PseudoResizer:
+    case CSSSelector::PseudoScrollbar:
+    case CSSSelector::PseudoScrollbarBack:
+    case CSSSelector::PseudoScrollbarButton:
+    case CSSSelector::PseudoScrollbarCorner:
+    case CSSSelector::PseudoScrollbarForward:
+    case CSSSelector::PseudoScrollbarThumb:
+    case CSSSelector::PseudoScrollbarTrack:
+    case CSSSelector::PseudoScrollbarTrackPiece:
+    case CSSSelector::PseudoWindowInactive:
+    case CSSSelector::PseudoCornerPresent:
+    case CSSSelector::PseudoDecrement:
+    case CSSSelector::PseudoIncrement:
+    case CSSSelector::PseudoHorizontal:
+    case CSSSelector::PseudoVertical:
+    case CSSSelector::PseudoStart:
+    case CSSSelector::PseudoEnd:
+    case CSSSelector::PseudoDoubleButton:
+    case CSSSelector::PseudoSingleButton:
+    case CSSSelector::PseudoNoButton:
+    case CSSSelector::PseudoSelection:
+    case CSSSelector::PseudoFullScreen:
+    case CSSSelector::PseudoFullScreenDocument:
+    case CSSSelector::PseudoFullScreenAncestor:
+    case CSSSelector::PseudoCue:
+    case CSSSelector::PseudoFutureCue:
+    case CSSSelector::PseudoPastCue:
+    case CSSSelector::PseudoContent:
+    case CSSSelector::PseudoSpatialNavigationFocus:
+        break;
+    case CSSSelector::PseudoNotParsed:
+    case CSSSelector::PseudoUnknown:
+    case CSSSelector::PseudoLeftPage:
+    case CSSSelector::PseudoRightPage:
+    case CSSSelector::PseudoFirstPage:
+        // These should not appear in StyleRule selectors.
+        ASSERT_NOT_REACHED();
+        break;
+    default:
+        // New pseudo type added. Figure out if it needs a subtree recalc or not.
+        ASSERT_NOT_REACHED();
+        break;
+    }
+}
+
+static bool requiresSubtreeRecalc(const CSSSelector& selector)
+{
+    if (!selector.matchesPseudoElement() && selector.match() != CSSSelector::PseudoClass) {
+        assertSupportedMatch(selector.match());
+        return false;
+    }
+
+    switch (selector.pseudoType()) {
+    case CSSSelector::PseudoFirstLine:
+        // :first-line pseudo can apply to elements arbitrarily deep down in the
+        // DOM from its container given an arbitrary number of block descendants
+        // with no inline flow content in between.
+    case CSSSelector::PseudoFirstLetter:
+        // :first-letter pseudo elements can be arbitrarily deep down in the
+        // DOM from its container given an arbitrary number of block descendants
+        // with no text content in between.
+    case CSSSelector::PseudoHostContext:
+        // :host-context matches a shadow host, yet the simple selectors inside
+        // :host-context matches an ancestor of the shadow host.
         return true;
     default:
+        assertSupportedPseudo(selector.pseudoType());
         return false;
     }
 }
@@ -118,80 +201,18 @@ void RuleFeature::trace(Visitor* visitor)
     visitor->trace(rule);
 }
 
-// This method is somewhat conservative in what it accepts.
-RuleFeatureSet::InvalidationSetMode RuleFeatureSet::invalidationSetModeForSelector(const CSSSelector& selector)
-{
-    bool foundCombinator = false;
-    bool foundIdent = false;
-    for (const CSSSelector* component = &selector; component; component = component->tagHistory()) {
-
-        if (component->match() == CSSSelector::Class || component->match() == CSSSelector::Id
-            || (component->match() == CSSSelector::Tag && component->tagQName().localName() != starAtom)
-            || component->isAttributeSelector() || component->isCustomPseudoElement()) {
-            if (!foundCombinator) {
-                // We have found an invalidation set feature in the rightmost compound selector.
-                foundIdent = true;
-            }
-        } else if (component->pseudoType() == CSSSelector::PseudoNot
-            || component->pseudoType() == CSSSelector::PseudoHost
-            || component->pseudoType() == CSSSelector::PseudoAny) {
-            if (const CSSSelectorList* selectorList = component->selectorList()) {
-                // Features inside :not() are not added to the feature set, so consider it a universal selector.
-                bool foundUniversal = component->pseudoType() == CSSSelector::PseudoNot;
-                for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector)) {
-                    // Find the invalidation set mode for each of the selectors in the selector list
-                    // of a :not(), :host(), etc. For instance, ".x :-webkit-any(.a, .b)" yields an
-                    // AddFeatures mode for both ".a" and ".b". ":-webkit-any(.a, *)" yields AddFeatures
-                    // for ".a", but UseSubtreeStyleChange for "*". One sub-selector without invalidation
-                    // set features is sufficient to cause the selector to be a universal selector as far
-                    // the invalidation set is concerned.
-                    InvalidationSetMode subSelectorMode = invalidationSetModeForSelector(*selector);
-
-                    // The sub-selector contained something unskippable, fall back to whole subtree
-                    // recalcs in collectFeaturesFromSelector. subSelectorMode will return
-                    // UseSubtreeStyleChange since there are no combinators inside the selector list,
-                    // so translate it to UseLocalStyleChange if a combinator has been seen in the
-                    // outer context.
-                    //
-                    // FIXME: Is UseSubtreeStyleChange ever needed as input to collectFeaturesFromSelector?
-                    // That is, are there any selectors for which we need to use SubtreeStyleChange for
-                    // changing features when present in the rightmost compound selector?
-                    if (subSelectorMode == UseSubtreeStyleChange)
-                        return foundCombinator ? UseLocalStyleChange : UseSubtreeStyleChange;
-
-                    // We found no features in the sub-selector, only skippable ones (foundIdent was
-                    // false at the end of this method). That is a universal selector as far as the
-                    // invalidation set is concerned.
-                    if (subSelectorMode == UseLocalStyleChange)
-                        foundUniversal = true;
-                }
-                if (!foundUniversal && !foundCombinator) {
-                    // All sub-selectors contained invalidation set features and
-                    // we are in the rightmost compound selector.
-                    foundIdent = true;
-                }
-            }
-        } else if (!isSkippableComponentForInvalidation(*component)) {
-            return foundCombinator ? UseLocalStyleChange : UseSubtreeStyleChange;
-        }
-        if (component->relation() != CSSSelector::SubSelector)
-            foundCombinator = true;
-    }
-    return foundIdent ? AddFeatures : UseLocalStyleChange;
-}
-
 void RuleFeatureSet::extractInvalidationSetFeature(const CSSSelector& selector, InvalidationSetFeatures& features)
 {
-    if (selector.match() == CSSSelector::Tag)
-        features.tagName = selector.tagQName().localName();
+    if (selector.match() == CSSSelector::Tag && selector.tagQName().localName() != starAtom)
+        features.setTagName(selector.tagQName().localName());
     else if (selector.match() == CSSSelector::Id)
-        features.id = selector.value();
+        features.setId(selector.value());
     else if (selector.match() == CSSSelector::Class)
-        features.classes.append(selector.value());
+        features.addClass(selector.value());
     else if (selector.isAttributeSelector())
-        features.attributes.append(selector.attribute().localName());
+        features.addAttribute(selector.attribute().localName());
     else if (selector.isCustomPseudoElement())
-        features.customPseudoElement = true;
+        features.setHasCustomPseudo();
 }
 
 RuleFeatureSet::RuleFeatureSet()
@@ -233,20 +254,17 @@ DescendantInvalidationSet* RuleFeatureSet::invalidationSetForSelector(const CSSS
 
 // Given a selector, update the descendant invalidation sets for the features found
 // in the selector. The first step is to extract the features from the rightmost
-// compound selector (extractInvalidationSetFeatures). Secondly, those features will be
-// added to the invalidation sets for the features found in the other compound selectors
-// (addFeaturesToInvalidationSets).
+// compound selector (extractInvalidationSetFeatures). Secondly, add those features
+// to the invalidation sets for the features found in the other compound selectors
+// (addFeaturesToInvalidationSets). If we find a feature in the right-most compound
+// selector that requires a subtree recalc, we addFeaturesToInvalidationSets for the
+// rightmost compound selector as well.
 
-RuleFeatureSet::InvalidationSetMode RuleFeatureSet::updateInvalidationSets(const CSSSelector& selector)
+void RuleFeatureSet::updateInvalidationSets(const CSSSelector& selector)
 {
-    InvalidationSetMode mode = invalidationSetModeForSelector(selector);
-    if (mode != AddFeatures)
-        return mode;
-
     InvalidationSetFeatures features;
     if (const CSSSelector* current = extractInvalidationSetFeatures(selector, features, false))
         addFeaturesToInvalidationSets(*current, features);
-    return AddFeatures;
 }
 
 const CSSSelector* RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelector& selector, InvalidationSetFeatures& features, bool negated)
@@ -254,30 +272,44 @@ const CSSSelector* RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelec
     for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
         if (!negated)
             extractInvalidationSetFeature(*current, features);
-        // Initialize the entry in the invalidation set map, if supported.
-        invalidationSetForSelector(*current);
-        if (current->pseudoType() == CSSSelector::PseudoHost || current->pseudoType() == CSSSelector::PseudoAny || current->pseudoType() == CSSSelector::PseudoNot) {
+        if (!invalidationSetForSelector(*current)) {
+            if (requiresSubtreeRecalc(*current)) {
+                // Fall back to use subtree invalidations, even for features in the
+                // rightmost compound selector. Returning the start &selector here
+                // will make addFeaturesToInvalidationSets start marking invalidation
+                // sets for subtree recalc for features in the rightmost compound
+                // selector.
+                features.hasFeatures = false;

[chrishtr, 2014/10/10 16:45:06]

It's a weird to trigger subtree by setting hasFeatures = false. Took me a while
to figure out what you were doing here.

+                return &selector;
+            }
             if (const CSSSelectorList* selectorList = current->selectorList()) {
-                for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
-                    extractInvalidationSetFeatures(*selector, features, current->pseudoType() == CSSSelector::PseudoNot);
+                const CSSSelector* subSelector = selectorList->first();
+                bool hadFeatures = features.hasFeatures;
+                bool allSubSelectorsHaveFeatures = !!subSelector;
+                for (; subSelector; subSelector = CSSSelectorList::next(*subSelector)) {
+                    features.hasFeatures = false;
+                    if (extractInvalidationSetFeatures(*subSelector, features, current->pseudoType() == CSSSelector::PseudoNot)) {
+                        // A non-null return means the sub-selector contained a selector
+                        // which requiresSubtreeRecalc(). Return the rightmost selector
+                        // to mark for subtree recalcs like above.
+                        ASSERT(!features.hasFeatures);
+                        return &selector;
+                    }
+                    allSubSelectorsHaveFeatures &= features.hasFeatures;
+                }
+                features.hasFeatures = hadFeatures || allSubSelectorsHaveFeatures;
             }
         }
 
-        switch (current->relation()) {
-        case CSSSelector::SubSelector:
-            break;
-        case CSSSelector::ShadowPseudo:
-        case CSSSelector::ShadowDeep:
+        if (current->relation() == CSSSelector::SubSelector)
+            continue;
+
+        if (current->isShadowSelector())
             features.treeBoundaryCrossing = true;
-            return current->tagHistory();
-        case CSSSelector::DirectAdjacent:
-        case CSSSelector::IndirectAdjacent:
-            features.wholeSubtree = true;
-            return current->tagHistory();
-        case CSSSelector::Descendant:
-        case CSSSelector::Child:
-            return current->tagHistory();
-        }
+
+        features.adjacent = current->isAdjacentSelector();
+
+        return current->tagHistory();
     }
     return 0;
 }
@@ -293,52 +325,51 @@ const CSSSelector* RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelec
 // As we encounter a descendant type of combinator, the features only need to be checked
 // against descendants in the same subtree only. Hence wholeSubtree is reset to false.
 
+void RuleFeatureSet::addFeaturesToInvalidationSet(DescendantInvalidationSet& invalidationSet, const InvalidationSetFeatures& features)
+{
+    if (features.treeBoundaryCrossing)
+        invalidationSet.setTreeBoundaryCrossing();
+    if (features.insertionPointCrossing)
+        invalidationSet.setInsertionPointCrossing();
+    if (features.useSubtreeInvalidation()) {
+        invalidationSet.setWholeSubtreeInvalid();
+        return;
+    }
+    if (!features.id.isEmpty())
+        invalidationSet.addId(features.id);
+    if (!features.tagName.isEmpty())
+        invalidationSet.addTagName(features.tagName);
+    for (const auto& className : features.classes)
+        invalidationSet.addClass(className);
+    for (const auto& attribute : features.attributes)
+        invalidationSet.addAttribute(attribute);
+    if (features.customPseudoElement)
+        invalidationSet.setCustomPseudoInvalid();
+}
+
 void RuleFeatureSet::addFeaturesToInvalidationSets(const CSSSelector& selector, InvalidationSetFeatures& features)
 {
     for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
         if (DescendantInvalidationSet* invalidationSet = invalidationSetForSelector(*current)) {
-            if (features.treeBoundaryCrossing)
-                invalidationSet->setTreeBoundaryCrossing();
-            if (features.wholeSubtree) {
-                invalidationSet->setWholeSubtreeInvalid();
-            } else {
-                if (!features.id.isEmpty())
-                    invalidationSet->addId(features.id);
-                if (!features.tagName.isEmpty())
-                    invalidationSet->addTagName(features.tagName);
-                for (Vector<AtomicString>::const_iterator it = features.classes.begin(); it != features.classes.end(); ++it)
-                    invalidationSet->addClass(*it);
-                for (Vector<AtomicString>::const_iterator it = features.attributes.begin(); it != features.attributes.end(); ++it)
-                    invalidationSet->addAttribute(*it);
-                if (features.customPseudoElement)
-                    invalidationSet->setCustomPseudoInvalid();
-            }
+            addFeaturesToInvalidationSet(*invalidationSet, features);
         } else {
-            if (current->pseudoType() == CSSSelector::PseudoHost)
+            if (current->isTreeBoundaryCrossing())
                 features.treeBoundaryCrossing = true;
+            if (current->isInsertionPointCrossing())
+                features.insertionPointCrossing = true;
             if (const CSSSelectorList* selectorList = current->selectorList()) {
-                ASSERT(current->pseudoType() == CSSSelector::PseudoHost || current->pseudoType() == CSSSelector::PseudoAny || current->pseudoType() == CSSSelector::PseudoNot);
                 for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
                     addFeaturesToInvalidationSets(*selector, features);
             }
         }
-        switch (current->relation()) {
-        case CSSSelector::SubSelector:
-            break;
-        case CSSSelector::ShadowPseudo:
-        case CSSSelector::ShadowDeep:
+
+        if (current->relation() == CSSSelector::SubSelector)
+            continue;
+
+        if (current->isShadowSelector())
             features.treeBoundaryCrossing = true;
-            features.wholeSubtree = false;
-            break;
-        case CSSSelector::Descendant:
-        case CSSSelector::Child:
-            features.wholeSubtree = false;
-            break;
-        case CSSSelector::DirectAdjacent:
-        case CSSSelector::IndirectAdjacent:
-            features.wholeSubtree = true;
-            break;
-        }
+
+        features.adjacent = current->isAdjacentSelector();
     }
 }
 
@@ -349,10 +380,10 @@ void RuleFeatureSet::addContentAttr(const AtomicString& attributeName)
 
 void RuleFeatureSet::collectFeaturesFromRuleData(const RuleData& ruleData)
 {
-    FeatureMetadata metadata;
-    InvalidationSetMode mode = updateInvalidationSets(ruleData.selector());
+    updateInvalidationSets(ruleData.selector());
 
-    collectFeaturesFromSelector(ruleData.selector(), metadata, mode);
+    FeatureMetadata metadata;
+    collectFeaturesFromSelector(ruleData.selector(), metadata);
     m_metadata.add(metadata);
 
     if (metadata.foundSiblingSelector)
@@ -393,17 +424,11 @@ DescendantInvalidationSet& RuleFeatureSet::ensurePseudoInvalidationSet(CSSSelect
     return *addResult.storedValue->value;
 }
 
-void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector, RuleFeatureSet::FeatureMetadata& metadata, InvalidationSetMode mode)
+void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector, RuleFeatureSet::FeatureMetadata& metadata)
 {
     unsigned maxDirectAdjacentSelectors = 0;
 
     for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
-        if (mode != AddFeatures) {
-            if (DescendantInvalidationSet* invalidationSet = invalidationSetForSelector(*current)) {
-                if (mode == UseSubtreeStyleChange)
-                    invalidationSet->setWholeSubtreeInvalid();
-            }
-        }
         if (current->pseudoType() == CSSSelector::PseudoFirstLine)
             metadata.usesFirstLineRules = true;
         if (current->isDirectAdjacentSelector()) {
@@ -416,24 +441,17 @@ void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector, Ru
         if (current->isSiblingSelector())
             metadata.foundSiblingSelector = true;
 
-        collectFeaturesFromSelectorList(current->selectorList(), metadata, mode);
+        const CSSSelectorList* selectorList = current->selectorList();
+        if (!selectorList)
+            continue;
 
-        if (mode == UseLocalStyleChange && current->relation() != CSSSelector::SubSelector)
-            mode = UseSubtreeStyleChange;
+        for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
+            collectFeaturesFromSelector(*selector, metadata);
     }
 
     ASSERT(!maxDirectAdjacentSelectors);
 }
 
-void RuleFeatureSet::collectFeaturesFromSelectorList(const CSSSelectorList* selectorList, RuleFeatureSet::FeatureMetadata& metadata, InvalidationSetMode mode)
-{
-    if (!selectorList)
-        return;
-
-    for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
-        collectFeaturesFromSelector(*selector, metadata, mode);
-}
-
 void RuleFeatureSet::FeatureMetadata::add(const FeatureMetadata& other)
 {
     usesFirstLineRules = usesFirstLineRules || other.usesFirstLineRules;
@@ -449,14 +467,14 @@ void RuleFeatureSet::FeatureMetadata::clear()
 
 void RuleFeatureSet::add(const RuleFeatureSet& other)
 {
-    for (InvalidationSetMap::const_iterator it = other.m_classInvalidationSets.begin(); it != other.m_classInvalidationSets.end(); ++it)
-        ensureClassInvalidationSet(it->key).combine(*it->value);
-    for (InvalidationSetMap::const_iterator it = other.m_attributeInvalidationSets.begin(); it != other.m_attributeInvalidationSets.end(); ++it)
-        ensureAttributeInvalidationSet(it->key).combine(*it->value);
-    for (InvalidationSetMap::const_iterator it = other.m_idInvalidationSets.begin(); it != other.m_idInvalidationSets.end(); ++it)
-        ensureIdInvalidationSet(it->key).combine(*it->value);
-    for (PseudoTypeInvalidationSetMap::const_iterator it = other.m_pseudoInvalidationSets.begin(); it != other.m_pseudoInvalidationSets.end(); ++it)
-        ensurePseudoInvalidationSet(static_cast<CSSSelector::PseudoType>(it->key)).combine(*it->value);
+    for (const auto& it : other.m_classInvalidationSets)
+        ensureClassInvalidationSet(it.key).combine(*it.value);
+    for (const auto& it : other.m_attributeInvalidationSets)
+        ensureAttributeInvalidationSet(it.key).combine(*it.value);
+    for (const auto& it : other.m_idInvalidationSets)
+        ensureIdInvalidationSet(it.key).combine(*it.value);
+    for (const auto& it : other.m_pseudoInvalidationSets)
+        ensurePseudoInvalidationSet(static_cast<CSSSelector::PseudoType>(it.key)).combine(*it.value);
 
     m_metadata.add(other.m_metadata);