Bug 1328420 Part 6: Implement ServoStyleSheet destructor. r=heycam

MozReview-Commit-ID: iVaza2s7d

--HG--
extra : rebase_source : 354979d2cb3d5ef95f2063f6c3a3c1dd3774c91f

layout/style/CSSStyleSheet.cpp

@@ -422,16 +422,8 @@ CSSStyleSheet::CSSStyleSheet(const CSSStyleSheet& aCopy,
 
 CSSStyleSheet::~CSSStyleSheet()
 {
-  for (StyleSheet* child = GetFirstChild();
-       child;
-       child = child->mNext) {
-    // XXXbz this is a little bogus; see the XXX comment where we
-    // declare mFirstChild.
-    if (child->mParent == this) {
-      child->mParent = nullptr;
-      child->mDocument = nullptr;
-    }
-  }
+  UnparentChildren();
+
   DropRuleCollection();
   mInner->RemoveSheet(this);
   // XXX The document reference is not reference counted and should

layout/style/ServoStyleSheet.cpp

@@ -29,6 +29,8 @@ ServoStyleSheet::ServoStyleSheet(css::SheetParsingMode aParsingMode,
 
 ServoStyleSheet::~ServoStyleSheet()
 {
+  UnparentChildren();
+
   DropSheet();
 }
 

layout/style/StyleSheet.cpp

@@ -308,6 +308,21 @@ StyleSheet::EnabledStateChanged()
 
 #undef FORWARD_INTERNAL
 
+void
+StyleSheet::UnparentChildren()
+{
+  // XXXbz this is a little bogus; see the XXX comment where we
+  // declare mFirstChild in StyleSheetInfo.
+  for (StyleSheet* child = GetFirstChild();
+       child;
+       child = child->mNext) {
+    if (child->mParent == this) {
+      child->mParent = nullptr;
+      child->mDocument = nullptr;
+    }
+  }
+}
+
 void
 StyleSheet::SubjectSubsumesInnerPrincipal(nsIPrincipal& aSubjectPrincipal,
                                           ErrorResult& aRv)

layout/style/StyleSheet.h

@@ -218,6 +218,8 @@ private:
                          ErrorResult& aRv);
 
 protected:
+  void UnparentChildren();
+
   // Return success if the subject principal subsumes the principal of our
   // inner, error otherwise.  This will also succeed if the subject has
   // UniversalXPConnect or if access is allowed by CORS.  In the latter case,
@@ -257,9 +259,11 @@ protected:
   friend class ::nsCSSRuleProcessor;
   friend struct mozilla::ChildSheetListBuilder;
 
-  // Make CSSStyleSheet a friend so it can access protected members of
-  // other StyleSheet objects (useful for iterating through children).
+  // Make CSSStyleSheet and ServoStyleSheet friends so they can access
+  // protected members of other StyleSheet objects (useful for iterating
+  // through children).
   friend class mozilla::CSSStyleSheet;
+  friend class mozilla::ServoStyleSheet;
 };
 
 } // namespace mozilla