Bug 1061469 - Part 2: ImportManager::AddLoaderWithNewURI should only return main referrers. r=mrbkap

content/base/src/ImportManager.cpp

@@ -742,6 +742,19 @@ nsRefPtr<ImportLoader> ImportManager::GetNearestPredecessor(nsINode* aNode)
   nsIDocument* doc = aNode->OwnerDoc();
   int32_t idx = doc->IndexOfSubImportLink(aNode);
   MOZ_ASSERT(idx != -1, "aNode must be a sub import link of its owner document");
+
+  for (; idx > 0; idx--) {
+    HTMLLinkElement* link =
+      static_cast<HTMLLinkElement*>(doc->GetSubImportLink(idx - 1));
+    nsCOMPtr<nsIURI> uri = link->GetHrefURI();
+    nsRefPtr<ImportLoader> ret;
+    mImports.Get(uri, getter_AddRefs(ret));
+    // Only main referrer links are interesting.
+    if (ret->GetMainReferrer() == link) {
+      return ret;
+    }
+  }
+
   if (idx == 0) {
     if (doc->IsMasterDocument()) {
       // If there is no previous one, and it was the master document, then
@@ -755,13 +768,8 @@ nsRefPtr<ImportLoader> ImportManager::GetNearestPredecessor(nsINode* aNode)
     nsCOMPtr<nsINode> mainReferrer = owner->GetMainReferrer();
     return GetNearestPredecessor(mainReferrer);
   }
-  MOZ_ASSERT(idx > 0);
-  HTMLLinkElement* link =
-    static_cast<HTMLLinkElement*>(doc->GetSubImportLink(idx - 1));
-  nsCOMPtr<nsIURI> uri = link->GetHrefURI();
-  nsRefPtr<ImportLoader> ret;
-  mImports.Get(uri, getter_AddRefs(ret));
-  return ret;
+
+  return nullptr;
 }
 
 } // namespace dom