Remove all implementation of CSSKeyframesMemoryReduction

Since we are not going to use CSSKeyframesMemoryReduction, this patch
removes all of its implementation.

Bug: 1141814
Change-Id: If531461761974d236e6456cd5745356e0caecf11
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2614839Reviewed-by: Rune Lillesveen <futhark@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841082}

third_party/blink/renderer/core/css/resolver/scoped_style_resolver.cc

@@ -59,9 +59,6 @@ ScopedStyleResolver* ScopedStyleResolver::Parent() const {
 }
 
 void ScopedStyleResolver::AddKeyframeRules(const RuleSet& rule_set) {
-  if (RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled())
-    return;
-
   const HeapVector<Member<StyleRuleKeyframes>> keyframes_rules =
       rule_set.KeyframesRules();
   for (auto rule : keyframes_rules)
@@ -148,42 +145,8 @@ void ScopedStyleResolver::ResetStyle() {
   needs_append_all_sheets_ = false;
 }
 
-const ActiveStyleSheetVector& ScopedStyleResolver::ActiveStyleSheets() {
-  StyleSheetCollection* collection =
-      GetTreeScope().GetDocument().GetStyleEngine().StyleSheetCollectionFor(
-          *scope_);
-  DCHECK(collection);
-  return collection->ActiveStyleSheets();
-}
-
-// static
-StyleRuleKeyframes*
-ScopedStyleResolver::KeyframeStylesForAnimationFromActiveSheets(
-    const AtomicString& name,
-    const ActiveStyleSheetVector& sheets) {
-  // We prefer non-vendor-prefixed over vendor-prefixed rules.
-  StyleRuleKeyframes* vendor_prefixed_result = nullptr;
-  for (auto sheet = sheets.rbegin(); sheet != sheets.rend(); ++sheet) {
-    RuleSet* rule_set = sheet->second;
-    if (!rule_set)
-      continue;
-    if (StyleRuleKeyframes* rule = rule_set->KeyframeStylesForAnimation(name)) {
-      if (!rule->IsVendorPrefixed())
-        return rule;
-      if (!vendor_prefixed_result)
-        vendor_prefixed_result = rule;
-    }
-  }
-  return vendor_prefixed_result;
-}
-
 StyleRuleKeyframes* ScopedStyleResolver::KeyframeStylesForAnimation(
     const AtomicString& animation_name) {
-  if (RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled()) {
-    return KeyframeStylesForAnimationFromActiveSheets(animation_name,
-                                                      ActiveStyleSheets());
-  }
-
   if (keyframes_rule_map_.IsEmpty())
     return nullptr;
 
@@ -195,7 +158,6 @@ StyleRuleKeyframes* ScopedStyleResolver::KeyframeStylesForAnimation(
 }
 
 void ScopedStyleResolver::AddKeyframeStyle(StyleRuleKeyframes* rule) {
-  DCHECK(!RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled());
   AtomicString name = rule->GetName();
 
   if (rule->IsVendorPrefixed()) {

third_party/blink/renderer/core/css/resolver/scoped_style_resolver.h

@@ -57,9 +57,6 @@ class CORE_EXPORT ScopedStyleResolver final
   const TreeScope& GetTreeScope() const { return *scope_; }
   ScopedStyleResolver* Parent() const;
 
-  static StyleRuleKeyframes* KeyframeStylesForAnimationFromActiveSheets(
-      const AtomicString& name,
-      const ActiveStyleSheetVector& sheets);
   StyleRuleKeyframes* KeyframeStylesForAnimation(
       const AtomicString& animation_name);
 
@@ -94,8 +91,6 @@ class CORE_EXPORT ScopedStyleResolver final
   void AddKeyframeRules(const RuleSet&);
   void AddKeyframeStyle(StyleRuleKeyframes*);
 
-  const ActiveStyleSheetVector& ActiveStyleSheets();
-
   CounterStyleMap& EnsureCounterStyleMap();
 
   Member<TreeScope> scope_;

third_party/blink/renderer/core/css/resolver/style_resolver_test.cc

@@ -1075,18 +1075,4 @@ TEST_F(StyleResolverTest, InheritStyleImagesFromDisplayContents) {
       << "-webkit-mask-image is fetched";
 }
 
-// https://crbug.com/1145406
-TEST_F(StyleResolverTest, StyleSheetWithNullRuleSet) {
-  ScopedCSSKeyframesMemoryReductionForTest enabled_scope(true);
-
-  GetDocument().documentElement()->setInnerHTML(R"HTML(
-    <style>.c6 { animation-name: anim; }</style>
-    <style media=print></style>
-    <div class=c6></div>
-  )HTML");
-
-  // Should not crash inside
-  UpdateAllLifecyclePhasesForTest();
-}
-
 }  // namespace blink

third_party/blink/renderer/core/css/rule_set.cc

@@ -339,50 +339,6 @@ void RuleSet::AddFontFaceRule(StyleRuleFontFace* rule) {
 void RuleSet::AddKeyframesRule(StyleRuleKeyframes* rule) {
   EnsurePendingRules();  // So that keyframes_rules_.ShrinkToFit() gets called.
   keyframes_rules_.push_back(rule);
-  keyframes_rules_sorted_ = false;
-}
-
-void RuleSet::SortKeyframesRulesIfNeeded() {
-  if (keyframes_rules_sorted_)
-    return;
-  // Sort keyframes rules by name, breaking ties with vendor prefixing.
-  // Since equal AtomicStrings always have the same impl, there's no need to
-  // actually compare the contents of two AtomicStrings. Comparing their impl
-  // addresses is enough.
-  std::stable_sort(
-      keyframes_rules_.begin(), keyframes_rules_.end(),
-      [](const StyleRuleKeyframes* lhs, const StyleRuleKeyframes* rhs) {
-        if (lhs->GetName() != rhs->GetName())
-          return lhs->GetName().Impl() < rhs->GetName().Impl();
-        if (lhs->IsVendorPrefixed() != rhs->IsVendorPrefixed())
-          return lhs->IsVendorPrefixed();
-        return false;
-      });
-  // Deduplicate rules, erase all but the last one for each animation name,
-  // since all the preceding ones are overridden.
-  auto boundary = std::unique(
-      keyframes_rules_.rbegin(), keyframes_rules_.rend(),
-      [](const StyleRuleKeyframes* lhs, const StyleRuleKeyframes* rhs) {
-        return lhs->GetName() == rhs->GetName();
-      });
-  keyframes_rules_.erase(keyframes_rules_.begin(), boundary.base());
-  keyframes_rules_.ShrinkToFit();
-  keyframes_rules_sorted_ = true;
-}
-
-StyleRuleKeyframes* RuleSet::KeyframeStylesForAnimation(
-    const AtomicString& name) {
-  SortKeyframesRulesIfNeeded();
-  Member<StyleRuleKeyframes>* rule_iterator = std::lower_bound(
-      keyframes_rules_.begin(), keyframes_rules_.end(), name,
-      [](const StyleRuleKeyframes* rule, const AtomicString& name) {
-        return rule->GetName().Impl() < name.Impl();
-      });
-  if (rule_iterator != keyframes_rules_.end() &&
-      (*rule_iterator)->GetName() == name) {
-    return *rule_iterator;
-  }
-  return nullptr;
 }
 
 void RuleSet::AddPropertyRule(StyleRuleProperty* rule) {

third_party/blink/renderer/core/css/rule_set.h

@@ -313,7 +313,6 @@ class CORE_EXPORT RuleSet final : public GarbageCollected<RuleSet> {
   const HeapVector<Member<StyleRuleKeyframes>>& KeyframesRules() const {
     return keyframes_rules_;
   }
-  StyleRuleKeyframes* KeyframeStylesForAnimation(const AtomicString& name);
   const HeapVector<Member<StyleRuleProperty>>& PropertyRules() const {
     return property_rules_;
   }
@@ -421,8 +420,6 @@ class CORE_EXPORT RuleSet final : public GarbageCollected<RuleSet> {
   HeapVector<MinimalRuleData> slotted_pseudo_element_rules_;
   Vector<MediaQuerySetResult> media_query_set_results_;
 
-  bool keyframes_rules_sorted_ = true;
-
   unsigned rule_count_;
   Member<PendingRuleMaps> pending_rules_;
 

third_party/blink/renderer/core/css/rule_set_test.cc

@@ -331,63 +331,6 @@ TEST(RuleSetTest, RuleCountNotIncreasedByInvalidRuleData) {
   EXPECT_EQ(1u, rule_set->RuleCount());
 }
 
-TEST(RuleSetTest, KeyframesRulesBasic) {
-  ScopedCSSKeyframesMemoryReductionForTest enabled_scope(true);
-
-  css_test_helpers::TestStyleSheet sheet;
-  sheet.AddCSSRules("@keyframes foo { from {top: 0;} to {top: 100px;} }");
-  sheet.AddCSSRules("@keyframes bar { from {top: 100px;} to {top: 0;} }");
-
-  RuleSet& rule_set = sheet.GetRuleSet();
-
-  StyleRuleKeyframes* foo = rule_set.KeyframeStylesForAnimation("foo");
-  EXPECT_TRUE(foo);
-  EXPECT_EQ("foo", foo->GetName());
-
-  StyleRuleKeyframes* bar = rule_set.KeyframeStylesForAnimation("bar");
-  EXPECT_TRUE(bar);
-  EXPECT_EQ("bar", bar->GetName());
-
-  StyleRuleKeyframes* nonexist =
-      rule_set.KeyframeStylesForAnimation("nonexist");
-  EXPECT_FALSE(nonexist);
-}
-
-TEST(RuleSetTest, KeyframesRulesOverriding) {
-  ScopedCSSKeyframesMemoryReductionForTest enabled_scope(true);
-
-  // Among multiple @keyframes rules with the same name, the last one wins.
-  css_test_helpers::TestStyleSheet sheet;
-  sheet.AddCSSRules("@keyframes foo { from1 {top: 0;} to1 {top: 100px;} }");
-  sheet.AddCSSRules("@keyframes foo { from2 {top: 100px;} to2 {top: 0;} }");
-
-  RuleSet& rule_set = sheet.GetRuleSet();
-
-  StyleRuleKeyframes* rule = rule_set.KeyframeStylesForAnimation("foo");
-  EXPECT_TRUE(rule);
-  EXPECT_EQ("foo", rule->GetName());
-
-  CSSKeyframesRule* css_rule = To<CSSKeyframesRule>(sheet.CssRules()->item(1));
-  EXPECT_EQ(rule, css_rule->Keyframes());
-}
-
-TEST(RuleSetTest, KeyframesRulesVendorPrefixed) {
-  ScopedCSSKeyframesMemoryReductionForTest enabled_scope(true);
-
-  // Non-vendor-prefixed keyframes rules win against vendor-prefixed ones.
-  css_test_helpers::TestStyleSheet sheet;
-  sheet.AddCSSRules("@keyframes foo { from1 {top: 0;} to1 {top: 100px;} }");
-  sheet.AddCSSRules(
-      "@-webkit-keyframes foo { from2 {top: 100px;} to2 {top: 0;} }");
-
-  RuleSet& rule_set = sheet.GetRuleSet();
-
-  StyleRuleKeyframes* rule = rule_set.KeyframeStylesForAnimation("foo");
-  EXPECT_TRUE(rule);
-  EXPECT_EQ("foo", rule->GetName());
-  EXPECT_FALSE(rule->IsVendorPrefixed());
-}
-
 TEST(RuleSetTest, UACounterStyleRules) {
   ScopedCSSAtRuleCounterStyleForTest enabled_scope(true);
 

third_party/blink/renderer/core/css/style_engine.cc

@@ -1893,9 +1893,6 @@ bool StyleEngine::AddUserFontFaceRules(const RuleSet& rule_set) {
 }
 
 void StyleEngine::AddUserKeyframeRules(const RuleSet& rule_set) {
-  if (RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled())
-    return;
-
   const HeapVector<Member<StyleRuleKeyframes>> keyframes_rules =
       rule_set.KeyframesRules();
   for (unsigned i = 0; i < keyframes_rules.size(); ++i)
@@ -1903,8 +1900,6 @@ void StyleEngine::AddUserKeyframeRules(const RuleSet& rule_set) {
 }
 
 void StyleEngine::AddUserKeyframeStyle(StyleRuleKeyframes* rule) {
-  DCHECK(!RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled());
-
   AtomicString animation_name(rule->GetName());
 
   if (rule->IsVendorPrefixed()) {
@@ -1941,11 +1936,6 @@ void StyleEngine::AddScrollTimelineRules(const RuleSet& rule_set) {
 
 StyleRuleKeyframes* StyleEngine::KeyframeStylesForAnimation(
     const AtomicString& animation_name) {
-  if (RuntimeEnabledFeatures::CSSKeyframesMemoryReductionEnabled()) {
-    return ScopedStyleResolver::KeyframeStylesForAnimationFromActiveSheets(
-        animation_name, active_user_style_sheets_);
-  }
-
   if (keyframes_rule_map_.IsEmpty())
     return nullptr;
 

third_party/blink/renderer/core/css/style_engine.h

@@ -418,8 +418,6 @@ class CORE_EXPORT StyleEngine final : public GarbageCollected<StyleEngine>,
   Color ForcedBackgroundColor() const { return forced_background_color_; }
   Color ColorAdjustBackgroundColor() const;
 
-  TreeScopeStyleSheetCollection* StyleSheetCollectionFor(TreeScope&);
-
   void Trace(Visitor*) const override;
   const char* NameInHeapSnapshot() const override { return "StyleEngine"; }
 
@@ -436,6 +434,7 @@ class CORE_EXPORT StyleEngine final : public GarbageCollected<StyleEngine>,
   }
 
   TreeScopeStyleSheetCollection& EnsureStyleSheetCollectionFor(TreeScope&);
+  TreeScopeStyleSheetCollection* StyleSheetCollectionFor(TreeScope&);
   bool ShouldUpdateDocumentStyleSheetCollection() const;
   bool ShouldUpdateShadowTreeStyleSheetCollection() const;
 

third_party/blink/renderer/platform/runtime_enabled_features.json5

@@ -526,14 +526,6 @@
       name: "CSSIndependentTransformProperties",
       status: "experimental",
     },
-    {
-      // Change ScopedStyleResolve and StyleEngine to use the already stored
-      // StyleSheetCollection to find @keyframes rules instead of creating their
-      // own hashmaps, so that we can save memory when there are web components
-      // with @keyframes rules in their stylesheets.
-      name: "CSSKeyframesMemoryReduction",
-      status: "test",
-    },
     {
       name: "CSSLayoutAPI",
       status: "experimental",