Bug 978833 patch 18 - Eliminate StyleRule::RuleMatched and call Declaration::SetImmutable directly for style rules (like for @page and keyframe rules). r=heycam

This is just simplification (plus the addition of an assertion).

--HG--
extra : commitid : 8jnKsQbG74s

dom/canvas/CanvasRenderingContext2D.cpp

@@ -2169,9 +2169,8 @@ CreateDeclaration(nsINode* aNode,
                          rule->GetDeclaration(), aChanged2, false);
   }
 
-  rule->RuleMatched();
-
   RefPtr<Declaration> declaration = rule->GetDeclaration();
+  declaration->SetImmutable();
   return declaration.forget();
 }
 

dom/svg/nsSVGElement.cpp

@@ -903,8 +903,9 @@ nsSVGElement::WalkContentStyleRules(nsRuleWalker* aRuleWalker)
     UpdateContentStyleRule();
 
   if (mContentStyleRule) {
-    mContentStyleRule->RuleMatched();
-    aRuleWalker->Forward(mContentStyleRule->GetDeclaration());
+    css::Declaration* declaration = mContentStyleRule->GetDeclaration();
+    declaration->SetImmutable();
+    aRuleWalker->Forward(declaration);
   }
 
   return NS_OK;
@@ -927,8 +928,9 @@ nsSVGElement::WalkAnimatedContentStyleRules(nsRuleWalker* aRuleWalker)
       animContentStyleRule = GetAnimatedContentStyleRule();
     }
     if (animContentStyleRule) {
-      animContentStyleRule->RuleMatched();
-      aRuleWalker->Forward(animContentStyleRule->GetDeclaration());
+      css::Declaration* declaration = animContentStyleRule->GetDeclaration();
+      declaration->SetImmutable();
+      aRuleWalker->Forward(declaration);
     }
   }
 }

layout/style/Declaration.h

@@ -72,9 +72,10 @@ private:
 // begins life in an invalid state which ends when InitializeEmpty or
 // CompressFrom is called upon it.  After that, it can be attached to
 // exactly one style rule, and will be destroyed when that style rule
-// is destroyed.  A declaration becomes immutable when its style rule's
-// |RuleMatched| method is called; after that, it must be copied before
-// it can be modified, which is taken care of by |EnsureMutable|.
+// is destroyed.  A declaration becomes immutable (via a SetImmutable
+// call) when it is matched (put in the rule tree); after that, it must
+// be copied before it can be modified, which is taken care of by
+// |EnsureMutable|.
 
 class Declaration final : public nsIStyleRule {
 public:
@@ -408,7 +409,7 @@ private:
   friend class ImportantStyleData;
   ImportantStyleData mImportantStyleData;
 
-  // set by style rules when |RuleMatched| is called;
+  // set when declaration put in the rule tree;
   // also by ToString (hence the 'mutable').
   mutable bool mImmutable;
 };

layout/style/StyleAnimationValue.cpp

@@ -2631,8 +2631,9 @@ StyleAnimationValue::ComputeValues(
 
     nsCOMArray<nsIStyleRule> ruleArray;
     ruleArray.AppendObject(styleSet->InitialStyleRule());
-    ruleArray.AppendObject(aStyleRule->GetDeclaration());
-    aStyleRule->RuleMatched();
+    css::Declaration* declaration = aStyleRule->GetDeclaration();
+    ruleArray.AppendObject(declaration);
+    declaration->SetImmutable();
     tmpStyleContext =
       styleSet->ResolveStyleByAddingRules(styleContext, ruleArray);
     if (!tmpStyleContext) {
@@ -2658,8 +2659,9 @@ StyleAnimationValue::ComputeValues(
   // value may have been biased by the 'initial' values supplied.
   if (!aIsContextSensitive || *aIsContextSensitive) {
     nsCOMArray<nsIStyleRule> ruleArray;
-    ruleArray.AppendObject(aStyleRule->GetDeclaration());
-    aStyleRule->RuleMatched();
+    css::Declaration* declaration = aStyleRule->GetDeclaration();
+    ruleArray.AppendObject(declaration);
+    declaration->SetImmutable();
     tmpStyleContext =
       styleSet->ResolveStyleByAddingRules(styleContext, ruleArray);
     if (!tmpStyleContext) {

layout/style/StyleRule.cpp

@@ -1447,12 +1447,6 @@ NS_INTERFACE_MAP_END
 NS_IMPL_ADDREF(StyleRule)
 NS_IMPL_RELEASE(StyleRule)
 
-void
-StyleRule::RuleMatched()
-{
-  mDeclaration->SetImmutable();
-}
-
 /* virtual */ int32_t
 StyleRule::GetType() const
 {

layout/style/StyleRule.h

@@ -327,12 +327,6 @@ public:
   already_AddRefed<StyleRule>
   DeclarationChanged(Declaration* aDecl, bool aHandleContainer);
 
-  /**
-   * The rule processor must call this method before calling
-   * nsRuleWalker::Forward on this rule during rule matching.
-   */
-  void RuleMatched();
-
   // hooks for DOM rule
   void GetCssText(nsAString& aCssText);
   void SetCssText(const nsAString& aCssText);

layout/style/nsCSSRuleProcessor.cpp

@@ -2618,9 +2618,9 @@ void ContentEnumFunc(const RuleValue& value, nsCSSSelector* aSelector,
                             nodeContext.mIsRelevantLink ?
                               SelectorMatchesTreeFlags(0) :
                               eLookForRelevantLink)) {
-      css::StyleRule *rule = value.mRule;
-      rule->RuleMatched();
-      data->mRuleWalker->Forward(rule->GetDeclaration());
+      css::Declaration* declaration = value.mRule->GetDeclaration();
+      declaration->SetImmutable();
+      data->mRuleWalker->Forward(declaration);
       // nsStyleSet will deal with the !important rule
     }
   }
@@ -2665,8 +2665,9 @@ nsCSSRuleProcessor::RulesMatching(AnonBoxRuleProcessorData* aData)
       nsTArray<RuleValue>& rules = entry->mRules;
       for (RuleValue *value = rules.Elements(), *end = value + rules.Length();
            value != end; ++value) {
-        value->mRule->RuleMatched();
-        aData->mRuleWalker->Forward(value->mRule->GetDeclaration());
+        css::Declaration* declaration = value->mRule->GetDeclaration();
+        declaration->SetImmutable();
+        aData->mRuleWalker->Forward(declaration);
       }
     }
   }

layout/style/nsHTMLCSSStyleSheet.cpp

@@ -67,8 +67,9 @@ nsHTMLCSSStyleSheet::ElementRulesMatching(nsPresContext* aPresContext,
   // just get the one and only style rule from the content's STYLE attribute
   css::StyleRule* rule = aElement->GetInlineStyleRule();
   if (rule) {
-    rule->RuleMatched();
-    aRuleWalker->Forward(rule->GetDeclaration());
+    css::Declaration* declaration = rule->GetDeclaration();
+    declaration->SetImmutable();
+    aRuleWalker->Forward(declaration);
   }
 
   rule = aElement->GetSMILOverrideStyleRule();
@@ -77,8 +78,9 @@ nsHTMLCSSStyleSheet::ElementRulesMatching(nsPresContext* aPresContext,
     if (!restyleManager->SkipAnimationRules()) {
       // Animation restyle (or non-restyle traversal of rules)
       // Now we can walk SMIL overrride style, without triggering transitions.
-      rule->RuleMatched();
-      aRuleWalker->Forward(rule->GetDeclaration());
+      css::Declaration* declaration = rule->GetDeclaration();
+      declaration->SetImmutable();
+      aRuleWalker->Forward(declaration);
     }
   }
 }
@@ -96,8 +98,9 @@ nsHTMLCSSStyleSheet::PseudoElementRulesMatching(Element* aPseudoElement,
   // just get the one and only style rule from the content's STYLE attribute
   css::StyleRule* rule = aPseudoElement->GetInlineStyleRule();
   if (rule) {
-    rule->RuleMatched();
-    aRuleWalker->Forward(rule->GetDeclaration());
+    css::Declaration* declaration = rule->GetDeclaration();
+    declaration->SetImmutable();
+    aRuleWalker->Forward(declaration);
   }
 }
 

layout/style/nsRuleNode.cpp

@@ -17,6 +17,8 @@
 #include "mozilla/Likely.h"
 #include "mozilla/LookAndFeel.h"
 
+#include "mozilla/css/Declaration.h"
+
 #include "nsAlgorithm.h" // for clamped()
 #include "nsRuleNode.h"
 #include "nscore.h"
@@ -50,6 +52,7 @@
 #include "nsCSSPropertySet.h"
 #include "mozilla/RuleNodeCacheConditions.h"
 #include "nsDeviceContext.h"
+#include "nsQueryObject.h"
 
 #if defined(_MSC_VER) || defined(__MINGW32__)
 #include <malloc.h>
@@ -1553,6 +1556,14 @@ nsRuleNode*
 nsRuleNode::Transition(nsIStyleRule* aRule, SheetType aLevel,
                        bool aIsImportantRule)
 {
+#ifdef DEBUG
+  {
+    RefPtr<css::Declaration> declaration(do_QueryObject(aRule));
+    MOZ_ASSERT(!declaration || !declaration->IsMutable(),
+               "caller must call Declaration::SetImmutable first");
+  }
+#endif
+
   nsRuleNode* next = nullptr;
   nsRuleNode::Key key(aRule, aLevel, aIsImportantRule);