--- a/layout/style/ServoPageRule.cpp
+++ b/layout/style/ServoPageRule.cpp
@@ -91,20 +91,20 @@ void
 ServoPageRuleDeclaration::GetCSSParsingEnvironment(
   CSSParsingEnvironment& aCSSParseEnv)
 {
   MOZ_ASSERT_UNREACHABLE("GetCSSParsingEnvironment "
                          "shouldn't be calling for a Servo rule");
   GetCSSParsingEnvironmentForRule(Rule(), aCSSParseEnv);
 }
 
-URLExtraData*
-ServoPageRuleDeclaration::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+ServoPageRuleDeclaration::GetServoCSSParsingEnvironment() const
 {
-  return GetURLDataForRule(Rule());
+  return GetServoCSSParsingEnvironmentForRule(Rule());
 }
 
 // -- ServoPageRule --------------------------------------------------
 
 ServoPageRule::ServoPageRule(RefPtr<RawServoPageRule> aRawRule)
   : CSSPageRule(0, 0)
   , mRawRule(Move(aRawRule))
   , mDecls(Servo_PageRule_GetStyle(mRawRule).Consume())

--- a/layout/style/ServoPageRule.h
+++ b/layout/style/ServoPageRule.h
@@ -27,17 +27,17 @@ public:
   NS_IMETHOD GetParentRule(nsIDOMCSSRule** aParent) final;
   nsINode* GetParentObject() final;
 
 protected:
   DeclarationBlock* GetCSSDeclaration(Operation aOperation) final;
   nsresult SetCSSDeclaration(DeclarationBlock* aDecl) final;
   nsIDocument* DocToUpdate() final;
   void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) final;
-  URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
 
 private:
   // For accessing the constructor.
   friend class ServoPageRule;
 
   explicit ServoPageRuleDeclaration(
     already_AddRefed<RawServoDeclarationBlock> aDecls);
   ~ServoPageRuleDeclaration();

--- a/layout/style/ServoStyleRule.cpp
+++ b/layout/style/ServoStyleRule.cpp
@@ -96,20 +96,20 @@ void
 ServoStyleRuleDeclaration::GetCSSParsingEnvironment(
   CSSParsingEnvironment& aCSSParseEnv)
 {
   MOZ_ASSERT_UNREACHABLE("GetCSSParsingEnvironment "
                          "shouldn't be calling for a Servo rule");
   GetCSSParsingEnvironmentForRule(Rule(), aCSSParseEnv);
 }
 
-URLExtraData*
-ServoStyleRuleDeclaration::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+ServoStyleRuleDeclaration::GetServoCSSParsingEnvironment() const
 {
-  return GetURLDataForRule(Rule());
+  return GetServoCSSParsingEnvironmentForRule(Rule());
 }
 
 // -- ServoStyleRule --------------------------------------------------
 
 ServoStyleRule::ServoStyleRule(already_AddRefed<RawServoStyleRule> aRawRule)
   : BindingStyleRule(0, 0)
   , mRawRule(aRawRule)
   , mDecls(Servo_StyleRule_GetStyle(mRawRule).Consume())

--- a/layout/style/ServoStyleRule.h
+++ b/layout/style/ServoStyleRule.h
@@ -28,17 +28,17 @@ public:
   NS_IMETHOD GetParentRule(nsIDOMCSSRule** aParent) final;
   nsINode* GetParentObject() final;
 
 protected:
   DeclarationBlock* GetCSSDeclaration(Operation aOperation) final;
   nsresult SetCSSDeclaration(DeclarationBlock* aDecl) final;
   nsIDocument* DocToUpdate() final;
   void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) final;
-  URLExtraData* GetURLData() const final;
+  ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
 
 private:
   // For accessing the constructor.
   friend class ServoStyleRule;
 
   explicit ServoStyleRuleDeclaration(
     already_AddRefed<RawServoDeclarationBlock> aDecls);
   ~ServoStyleRuleDeclaration();

--- a/layout/style/StyleRule.cpp
+++ b/layout/style/StyleRule.cpp
@@ -1057,17 +1057,17 @@ protected:
 
 public:
   explicit DOMCSSDeclarationImpl(css::StyleRule *aRule);
 
   NS_IMETHOD GetParentRule(nsIDOMCSSRule **aParent) override;
   virtual DeclarationBlock* GetCSSDeclaration(Operation aOperation) override;
   virtual nsresult SetCSSDeclaration(DeclarationBlock* aDecl) override;
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) override;
-  URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
   virtual nsIDocument* DocToUpdate() override;
 
   // Override |AddRef| and |Release| for being owned by StyleRule.  Also, we
   // need to forward QI for cycle collection things to StyleRule.
   NS_DECL_ISUPPORTS_INHERITED
 
   virtual nsINode *GetParentObject() override
   {
@@ -1116,21 +1116,20 @@ DOMCSSDeclarationImpl::GetCSSDeclaration
 }
 
 void
 DOMCSSDeclarationImpl::GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv)
 {
   GetCSSParsingEnvironmentForRule(mRule, aCSSParseEnv);
 }
 
-URLExtraData*
-DOMCSSDeclarationImpl::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+DOMCSSDeclarationImpl::GetServoCSSParsingEnvironment() const
 {
-  MOZ_ASSERT_UNREACHABLE("GetURLData shouldn't be calling on a Gecko rule");
-  return GetURLDataForRule(mRule);
+  MOZ_CRASH("GetURLData shouldn't be calling on a Gecko rule");
 }
 
 NS_IMETHODIMP
 DOMCSSDeclarationImpl::GetParentRule(nsIDOMCSSRule **aParent)
 {
   NS_ENSURE_ARG_POINTER(aParent);
 
   NS_IF_ADDREF(*aParent = mRule);

--- a/layout/style/nsCSSRules.cpp
+++ b/layout/style/nsCSSRules.cpp
@@ -1621,21 +1621,20 @@ nsCSSKeyframeStyleDeclaration::GetCSSDec
 }
 
 void
 nsCSSKeyframeStyleDeclaration::GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv)
 {
   GetCSSParsingEnvironmentForRule(mRule, aCSSParseEnv);
 }
 
-URLExtraData*
-nsCSSKeyframeStyleDeclaration::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+nsCSSKeyframeStyleDeclaration::GetServoCSSParsingEnvironment() const
 {
-  MOZ_ASSERT_UNREACHABLE("GetURLData shouldn't be calling on a Gecko rule");
-  return GetURLDataForRule(mRule);
+  MOZ_CRASH("GetURLData shouldn't be calling on a Gecko rule");
 }
 
 NS_IMETHODIMP
 nsCSSKeyframeStyleDeclaration::GetParentRule(nsIDOMCSSRule **aParent)
 {
   NS_ENSURE_ARG_POINTER(aParent);
 
   NS_IF_ADDREF(*aParent = mRule);
@@ -2138,21 +2137,20 @@ nsCSSPageStyleDeclaration::GetCSSDeclara
 }
 
 void
 nsCSSPageStyleDeclaration::GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv)
 {
   GetCSSParsingEnvironmentForRule(mRule, aCSSParseEnv);
 }
 
-URLExtraData*
-nsCSSPageStyleDeclaration::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+nsCSSPageStyleDeclaration::GetServoCSSParsingEnvironment() const
 {
-  MOZ_ASSERT_UNREACHABLE("GetURLData shouldn't be calling on a Gecko rule");
-  return GetURLDataForRule(mRule);
+  MOZ_CRASH("GetURLData shouldn't be calling on a Gecko rule");
 }
 
 NS_IMETHODIMP
 nsCSSPageStyleDeclaration::GetParentRule(nsIDOMCSSRule** aParent)
 {
   NS_ENSURE_ARG_POINTER(aParent);
 
   NS_IF_ADDREF(*aParent = mRule);

--- a/layout/style/nsCSSRules.h
+++ b/layout/style/nsCSSRules.h
@@ -243,17 +243,17 @@ class nsCSSKeyframeStyleDeclaration fina
 public:
   explicit nsCSSKeyframeStyleDeclaration(nsCSSKeyframeRule *aRule);
 
   NS_IMETHOD GetParentRule(nsIDOMCSSRule **aParent) override;
   void DropReference() { mRule = nullptr; }
   virtual mozilla::DeclarationBlock* GetCSSDeclaration(Operation aOperation) override;
   virtual nsresult SetCSSDeclaration(mozilla::DeclarationBlock* aDecl) override;
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) override;
-  mozilla::URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
   virtual nsIDocument* DocToUpdate() override;
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(nsCSSKeyframeStyleDeclaration,
                                                          nsICSSDeclaration)
 
   virtual nsINode* GetParentObject() override;
 
@@ -384,17 +384,17 @@ class nsCSSPageStyleDeclaration final : 
 public:
   explicit nsCSSPageStyleDeclaration(nsCSSPageRule *aRule);
 
   NS_IMETHOD GetParentRule(nsIDOMCSSRule **aParent) override;
   void DropReference() { mRule = nullptr; }
   virtual mozilla::DeclarationBlock* GetCSSDeclaration(Operation aOperation) override;
   virtual nsresult SetCSSDeclaration(mozilla::DeclarationBlock* aDecl) override;
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) override;
-  mozilla::URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
   virtual nsIDocument* DocToUpdate() override;
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(nsCSSPageStyleDeclaration,
                                                          nsICSSDeclaration)
 
   virtual nsINode *GetParentObject() override;
 

--- a/layout/style/nsComputedDOMStyle.cpp
+++ b/layout/style/nsComputedDOMStyle.cpp
@@ -710,21 +710,20 @@ nsComputedDOMStyle::DocToUpdate()
 void
 nsComputedDOMStyle::GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv)
 {
   NS_RUNTIMEABORT("called nsComputedDOMStyle::GetCSSParsingEnvironment");
   // Just in case NS_RUNTIMEABORT ever stops killing us for some reason
   aCSSParseEnv.mPrincipal = nullptr;
 }
 
-URLExtraData*
-nsComputedDOMStyle::GetURLData() const
-{
-  NS_RUNTIMEABORT("called nsComputedDOMStyle::GetURLData");
-  return nullptr;
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+nsComputedDOMStyle::GetServoCSSParsingEnvironment() const
+{
+  MOZ_CRASH("called nsComputedDOMStyle::GetServoCSSParsingEnvironment");
 }
 
 void
 nsComputedDOMStyle::ClearStyleContext()
 {
   if (mResolvedStyleContext) {
     mResolvedStyleContext = false;
     mContent->RemoveMutationObserver(this);

--- a/layout/style/nsComputedDOMStyle.h
+++ b/layout/style/nsComputedDOMStyle.h
@@ -121,17 +121,17 @@ public:
 
   // nsDOMCSSDeclaration abstract methods which should never be called
   // on a nsComputedDOMStyle object, but must be defined to avoid
   // compile errors.
   virtual mozilla::DeclarationBlock* GetCSSDeclaration(Operation) override;
   virtual nsresult SetCSSDeclaration(mozilla::DeclarationBlock*) override;
   virtual nsIDocument* DocToUpdate() override;
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) override;
-  mozilla::URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
 
   static already_AddRefed<nsROCSSPrimitiveValue>
     MatrixToCSSValue(const mozilla::gfx::Matrix4x4& aMatrix);
 
   static void RegisterPrefChangeCallbacks();
   static void UnregisterPrefChangeCallbacks();
 
   // nsIMutationObserver

--- a/layout/style/nsDOMCSSAttrDeclaration.cpp
+++ b/layout/style/nsDOMCSSAttrDeclaration.cpp
@@ -168,20 +168,22 @@ nsDOMCSSAttributeDeclaration::GetCSSPars
 
   nsIDocument* doc = mElement->OwnerDoc();
   aCSSParseEnv.mSheetURI = doc->GetDocumentURI();
   aCSSParseEnv.mBaseURI = mElement->GetBaseURIForStyleAttr();
   aCSSParseEnv.mPrincipal = mElement->NodePrincipal();
   aCSSParseEnv.mCSSLoader = doc->CSSLoader();
 }
 
-URLExtraData*
-nsDOMCSSAttributeDeclaration::GetURLData() const
+nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+nsDOMCSSAttributeDeclaration::GetServoCSSParsingEnvironment() const
 {
-  return mElement->GetURLDataForStyleAttr();
+  ServoCSSParsingEnvironment parsingEnv(mElement->GetURLDataForStyleAttr(),
+    mElement->OwnerDoc()->GetCompatibilityMode());
+  return parsingEnv;
 }
 
 NS_IMETHODIMP
 nsDOMCSSAttributeDeclaration::GetParentRule(nsIDOMCSSRule **aParent)
 {
   NS_ENSURE_ARG_POINTER(aParent);
 
   *aParent = nullptr;

--- a/layout/style/nsDOMCSSAttrDeclaration.h
+++ b/layout/style/nsDOMCSSAttrDeclaration.h
@@ -27,17 +27,17 @@ public:
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
   NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS_AMBIGUOUS(nsDOMCSSAttributeDeclaration,
                                                                    nsICSSDeclaration)
 
   // If GetCSSDeclaration returns non-null, then the decl it returns
   // is owned by our current style rule.
   virtual mozilla::DeclarationBlock* GetCSSDeclaration(Operation aOperation) override;
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) override;
-  mozilla::URLExtraData* GetURLData() const final;
+  nsDOMCSSDeclaration::ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const final;
   NS_IMETHOD GetParentRule(nsIDOMCSSRule **aParent) override;
 
   virtual nsINode* GetParentObject() override;
 
   NS_IMETHOD SetPropertyValue(const nsCSSPropertyID aPropID,
                               const nsAString& aValue) override;
 
 protected:

--- a/layout/style/nsDOMCSSDeclaration.cpp
+++ b/layout/style/nsDOMCSSDeclaration.cpp
@@ -111,47 +111,44 @@ nsDOMCSSDeclaration::SetCssText(const ns
 {
   // We don't need to *do* anything with the old declaration, but we need
   // to ensure that it exists, or else SetCSSDeclaration may crash.
   DeclarationBlock* olddecl = GetCSSDeclaration(eOperation_Modify);
   if (!olddecl) {
     return NS_ERROR_NOT_AVAILABLE;
   }
 
-  CSSParsingEnvironment env;
-  URLExtraData* urlData = nullptr;
-  if (olddecl->IsGecko()) {
-    GetCSSParsingEnvironment(env);
-    if (!env.mPrincipal) {
-      return NS_ERROR_NOT_AVAILABLE;
-    }
-  } else {
-    urlData = GetURLData();
-    if (!urlData) {
-      return NS_ERROR_NOT_AVAILABLE;
-    }
-  }
-
   // For nsDOMCSSAttributeDeclaration, SetCSSDeclaration will lead to
   // Attribute setting code, which leads in turn to BeginUpdate.  We
   // need to start the update now so that the old rule doesn't get used
   // between when we mutate the declaration and when we set the new
   // rule (see stack in bug 209575).
   mozAutoDocConditionalContentUpdateBatch autoUpdate(DocToUpdate(), true);
 
   RefPtr<DeclarationBlock> newdecl;
   if (olddecl->IsServo()) {
-    newdecl = ServoDeclarationBlock::FromCssText(aCssText, urlData);
+    ServoCSSParsingEnvironment servoEnv = GetServoCSSParsingEnvironment();
+    if (!servoEnv.mUrlExtraData) {
+      return NS_ERROR_NOT_AVAILABLE;
+    }
+
+    newdecl = ServoDeclarationBlock::FromCssText(aCssText, servoEnv.mUrlExtraData);
   } else {
+    CSSParsingEnvironment geckoEnv;
+    GetCSSParsingEnvironment(geckoEnv);
+    if (!geckoEnv.mPrincipal) {
+      return NS_ERROR_NOT_AVAILABLE;
+    }
+
     RefPtr<css::Declaration> decl(new css::Declaration());
     decl->InitializeEmpty();
-    nsCSSParser cssParser(env.mCSSLoader);
+    nsCSSParser cssParser(geckoEnv.mCSSLoader);
     bool changed;
-    nsresult result = cssParser.ParseDeclarations(aCssText, env.mSheetURI,
-                                                  env.mBaseURI, env.mPrincipal,
+    nsresult result = cssParser.ParseDeclarations(aCssText, geckoEnv.mSheetURI,
+                                                  geckoEnv.mBaseURI, geckoEnv.mPrincipal,
                                                   decl, &changed);
     if (NS_FAILED(result) || !changed) {
       return result;
     }
     newdecl = decl.forget();
   }
 
   return SetCSSDeclaration(newdecl);
@@ -277,62 +274,67 @@ nsDOMCSSDeclaration::GetCSSParsingEnviro
 
   nsIDocument* document = sheet->GetAssociatedDocument();
   aCSSParseEnv.mSheetURI = sheet->GetSheetURI();
   aCSSParseEnv.mBaseURI = sheet->GetBaseURI();
   aCSSParseEnv.mPrincipal = sheet->Principal();
   aCSSParseEnv.mCSSLoader = document ? document->CSSLoader() : nullptr;
 }
 
-/* static */ URLExtraData*
-nsDOMCSSDeclaration::GetURLDataForRule(const css::Rule* aRule)
+/* static */ nsDOMCSSDeclaration::ServoCSSParsingEnvironment
+nsDOMCSSDeclaration::GetServoCSSParsingEnvironmentForRule(const css::Rule* aRule)
 {
-  if (StyleSheet* sheet = aRule ? aRule->GetStyleSheet() : nullptr) {
-    return sheet->AsServo()->URLData();
+  StyleSheet* sheet = aRule ? aRule->GetStyleSheet() : nullptr;
+  if (!sheet) {
+    return ServoCSSParsingEnvironment(nullptr, eCompatibility_FullStandards);
   }
-  return nullptr;
+
+  if (nsIDocument* document = aRule->GetDocument()) {
+    return ServoCSSParsingEnvironment(sheet->AsServo()->URLData(),
+      document->GetCompatibilityMode());
+  } else {
+    return ServoCSSParsingEnvironment(sheet->AsServo()->URLData(),
+                                      eCompatibility_FullStandards);
+  }
 }
 
 template<typename GeckoFunc, typename ServoFunc>
 nsresult
 nsDOMCSSDeclaration::ModifyDeclaration(GeckoFunc aGeckoFunc,
                                        ServoFunc aServoFunc)
 {
   DeclarationBlock* olddecl = GetCSSDeclaration(eOperation_Modify);
   if (!olddecl) {
     return NS_ERROR_NOT_AVAILABLE;
   }
 
-  CSSParsingEnvironment env;
-  URLExtraData* urlData = nullptr;
-  if (olddecl->IsGecko()) {
-    GetCSSParsingEnvironment(env);
-    if (!env.mPrincipal) {
-      return NS_ERROR_NOT_AVAILABLE;
-    }
-  } else {
-    urlData = GetURLData();
-    if (!urlData) {
-      return NS_ERROR_NOT_AVAILABLE;
-    }
-  }
-
   // For nsDOMCSSAttributeDeclaration, SetCSSDeclaration will lead to
   // Attribute setting code, which leads in turn to BeginUpdate.  We
   // need to start the update now so that the old rule doesn't get used
   // between when we mutate the declaration and when we set the new
   // rule (see stack in bug 209575).
   mozAutoDocConditionalContentUpdateBatch autoUpdate(DocToUpdate(), true);
   RefPtr<DeclarationBlock> decl = olddecl->EnsureMutable();
 
   bool changed;
   if (decl->IsGecko()) {
-    aGeckoFunc(decl->AsGecko(), env, &changed);
+    CSSParsingEnvironment geckoEnv;
+    GetCSSParsingEnvironment(geckoEnv);
+    if (!geckoEnv.mPrincipal) {
+      return NS_ERROR_NOT_AVAILABLE;
+    }
+
+    aGeckoFunc(decl->AsGecko(), geckoEnv, &changed);
   } else {
-    changed = aServoFunc(decl->AsServo(), urlData);
+    ServoCSSParsingEnvironment servoEnv = GetServoCSSParsingEnvironment();
+    if (!servoEnv.mUrlExtraData) {
+      return NS_ERROR_NOT_AVAILABLE;
+    }
+
+    changed = aServoFunc(decl->AsServo(), servoEnv.mUrlExtraData);
   }
   if (!changed) {
     // Parsing failed -- but we don't throw an exception for that.
     return NS_OK;
   }
 
   return SetCSSDeclaration(decl);
 }

--- a/layout/style/nsDOMCSSDeclaration.h
+++ b/layout/style/nsDOMCSSDeclaration.h
@@ -141,32 +141,44 @@ protected:
     nsIPrincipal* MOZ_UNSAFE_REF("user of CSSParsingEnviroment must hold an owning "
                                  "reference; reference counting here has unacceptable "
                                  "performance overhead (see bug 649163)") mPrincipal;
     mozilla::css::Loader* MOZ_UNSAFE_REF("user of CSSParsingEnviroment must hold an owning "
                                          "reference; reference counting here has unacceptable "
                                          "performance overhead (see bug 649163)") mCSSLoader;
   };
 
+  // Information neded to parse a declaration for Servo side.
+  struct MOZ_STACK_CLASS ServoCSSParsingEnvironment {
+    mozilla::URLExtraData* mUrlExtraData;
+    nsCompatibility mCompatMode;
+
+    ServoCSSParsingEnvironment(mozilla::URLExtraData* aUrlData, nsCompatibility aCompatMode)
+      : mUrlExtraData(aUrlData), mCompatMode(aCompatMode) {}
+  };
+
   // On failure, mPrincipal should be set to null in aCSSParseEnv.
   // If mPrincipal is null, the other members may not be set to
   // anything meaningful.
   virtual void GetCSSParsingEnvironment(CSSParsingEnvironment& aCSSParseEnv) = 0;
 
+  // mUrlExtraData returns URL data for parsing url values in
+  // CSS. Returns nullptr on failure. If mUrlExtraData is nullptr,
+  // mCompatMode may not be set to anything meaningful.
+  virtual ServoCSSParsingEnvironment GetServoCSSParsingEnvironment() const = 0;
+
   // An implementation for GetCSSParsingEnvironment for callers wrapping
   // an css::Rule.
   static void GetCSSParsingEnvironmentForRule(mozilla::css::Rule* aRule,
                                               CSSParsingEnvironment& aCSSParseEnv);
 
-  // An implementation for GetURLData for callers wrapping a css::Rule.
-  static mozilla::URLExtraData* GetURLDataForRule(const mozilla::css::Rule* aRule);
-
-  // Returns URL data for parsing url values in CSS.
-  // Returns nullptr on failure.
-  virtual mozilla::URLExtraData* GetURLData() const = 0;
+  // An implementation for GetServoCSSParsingEnvironment for callers wrapping
+  // an css::Rule.
+  static ServoCSSParsingEnvironment
+    GetServoCSSParsingEnvironmentForRule(const mozilla::css::Rule* aRule);
 
   nsresult ParsePropertyValue(const nsCSSPropertyID aPropID,
                               const nsAString& aPropValue,
                               bool aIsImportant);
 
   nsresult ParseCustomPropertyValue(const nsAString& aPropertyName,
                                     const nsAString& aPropValue,
                                     bool aIsImportant);