Bug 1368690: Move EnsureUniqueInner call after all the members have been initialized. r=xidorn

MozReview-Commit-ID: GoeLsjSAU00

layout/style/CSSStyleSheet.cpp

@@ -361,6 +361,15 @@ CSSStyleSheet::CSSStyleSheet(const CSSStyleSheet& aCopy,
     mRuleProcessors(nullptr)
 {
   mParent = aParentToUse;
+
+  if (mDirty) { // CSSOM's been there, force full copy now
+    NS_ASSERTION(mInner->mComplete, "Why have rules been accessed on an incomplete sheet?");
+    // FIXME: handle failure?
+    //
+    // NOTE: It's important to call this from the subclass, since it could
+    // access uninitialized members otherwise.
+    EnsureUniqueInner();
+  }
 }
 
 CSSStyleSheet::~CSSStyleSheet()

layout/style/ServoStyleSheet.cpp

@@ -87,6 +87,15 @@ ServoStyleSheet::ServoStyleSheet(const ServoStyleSheet& aCopy,
   : StyleSheet(aCopy, aOwnerRuleToUse, aDocumentToUse, aOwningNodeToUse)
 {
   mParent = aParentToUse;
+
+  if (mDirty) { // CSSOM's been there, force full copy now
+    NS_ASSERTION(mInner->mComplete, "Why have rules been accessed on an incomplete sheet?");
+    // FIXME: handle failure?
+    //
+    // NOTE: It's important to call this from the subclass, since this could
+    // access uninitialized members otherwise.
+    EnsureUniqueInner();
+  }
 }
 
 ServoStyleSheet::~ServoStyleSheet()

layout/style/StyleSheet.cpp

@@ -54,12 +54,6 @@ StyleSheet::StyleSheet(const StyleSheet& aCopy,
   MOZ_ASSERT(mInner, "Should only copy StyleSheets with an mInner.");
   mInner->AddSheet(this);
 
-  if (mDirty) { // CSSOM's been there, force full copy now
-    NS_ASSERTION(mInner->mComplete, "Why have rules been accessed on an incomplete sheet?");
-    // FIXME: handle failure?
-    EnsureUniqueInner();
-  }
-
   if (aCopy.mMedia) {
     // XXX This is wrong; we should be keeping @import rules and
     // sheets in sync!